Update: I've tested additional sets Edifier Stax S3, Sony XM4, XM5, Bose QC Ultra and NC 700.
Summary.... NC700 is a much better buy with equivalent (albeit slightly different) sound quality.

Sound Quality: PX8 > NC700 > PX7 S2e = XM4 > XM5 > QC Ultra > PX7 S2 >>>>> Stax S3
I fell in love with the sound signature and clarity of the PX8. Music just comes alive. It delivers music in a way that you can be isolated from the outside world and concentrate on the music. No matter how you look at it shelling out $680 is a tough pill to swallow; this is where the Bose QC45, NC700; Sony XM5; and the PX7 S2 come in. The PX7 S2 sound quality is no slouch by any means, but it fails to deliver music the way the PX8 does. It didn't trigger my brain to release dopamine at the same level as the PX8. The S2e comes very close; very very close. The bass is slightly less definitive (more muddled) and the trebble slightly less nuanced. For a difference of $280, I think it's an acceptable difference.
The microphone quality is on par with the PX8. Voice comes out well, with a nice level of mids and lows. It's not podcast mic quality, but it's super good.

Comfort: PX8 > NC700 > XM5 > XM4 > QC Ultra >> PX7 S2e = PX7 S2 > Stax S3
The comfort however, is a different story altogether. The PX8 is heavy. But the clamping force never bothers me the way the PX7 S2 and S2e do. Clamping force is just too much when combined with the faux leather material which retain heat better than the supple leather of the PX8. For $400, this is not acceptable. They should take a page in ergonomics from Bose.

As much as I loved the P7s, they weren't very comfortable and when I went full-time glasses they got worse. I was researching headphones for months with a focus on the Sony XM5. Don't get me wrong, they're great headphones and I read tons of great reviews on them. I also have buyers remorse so was worried about an XM6 knowing my luck. I was close to purchasing the PX7 S2 then these miraculously were released.

Bought these in Ocean Blue. Very comfortable and really well constructed. With glasses on all the time they are not squeezing the frames against my head. The noise cancelling is a must for the Long Island Railroad and NYC Subway. The sound quality is amazing, it's rich with great bass and I'm hearing sounds I missed out on with the P7s. The battery life is amazing and the headphones charge quickly. The case is large but somewhat flat so it fits perfectly into a backpack for my commute. I've been showing them off to coworkers who need headphones, but of course the Apple obsession exists so many were leading to the AirPods Max. A few tried these and have changed their minds.

I listen to a ton of EDM from the classic Chicane to Armin Van Buren and a ton of Drum and Bass. I also love Rock and Pop as well as tons of 80s/90s. These have been great for all music types.

As a part time audiophile, I do search for products that I find eye opening at less than painful price range. I'm not about to delve into the world of upper echelons of audio due to financial reasons but I found these headphones to be impressive. I'm a wired-headphone kinda guy. They do, by fact and science, sound better. These being wireless and sounding the way they do is what caught my attention. I've never owned any B&W products. Now they have a customer for life. Apparently these have the ability to be listened to wired as well, I have yet to try it.
Now, one thing has caught my attention (which I provide a photo). I don't know if I got an opposite of a lemon device or what but I'd consider this a golden apple. I've used these at my job almost every day. I've had these since September 5th. I haven't charged them ONCE. They still haven't died. I'd say the battery is life is incredible on these.
The sound quality is very good. Being wireless and battery powered, they aren't as loud as I'd like it, but that's only because, again, I have wired headphones I use on my PreSonus Central Station (Philips Fidelios, Beats Pro *the all metal ones, not those plastic pos*). You can hear the power behind it as far as volume and detail. But nonetheless they do sound ALMOST on par with the wired headphones I have, so very very nice.
I haven't had much experience with noise cancellation so I don't have much of an opinion on it. But so far, these are the best I've had.
And lastly. Their appearance. They just look good. I love the color, design, shape, and feel. They are comfortable. I was worried about some of the reviews with the quality control/build issues, but I could care less honestly. As long as they play music at their intended quality, I'm happy.

The hype and internet consensus is justified: the Px7 S2s sound phenomenal. I prefer the soundstage over that of my Sony WH-1000XM5s, which I use for calls and on flights (or in other noisy situations), since their noise cancellation and microphones are definitely better than those on the Px7 S2. Compared to the Px7 S2s, the XM5s sound muddy and condensed, whereas the Px7 S2s feel expansive and crisp, while maintaining a robust lower register of bass to fill out the overall soundstage.

I'll cover 5 main areas in this review, often comparing the Px7 S2s to my experience with the Sony WH-1000XM5s (XM5s), the Airpods Max's (APMs), and the first-generation B&W Px7s:

1. Sound Quality
2. Build Quality
3. Bluetooth & Corded Connection Technology
4. Included Case
5. New Bowers & Wilkins App

"” SOUND QUALITY "”
I should preface this by saying that I purchased the Px7 S2s to be my listen-at-home-for-best-sound-quality-using-bluetooth headphones. I have a pair of open-back Beyerdynamic 990s that I use to mix and produce music, my XM5s for traveling and phone/video calls, the APMs (which I've since returned), the in-ear Sony WF-1000XM4s for the gym and exercising, and now these new Px7 S2s from B&W (which I'll just call "S2s" from here on).

It took a little time for the S2s to "run in", basically like "breaking in" any pair of headphones, over the course of about 24 hours of listening time "“ and the sound really just got better and better. I noticed better channel separation over time, especially when listening via the corded connection and internal DAC to get true HiFi sound (using TIDAL).

I did adjust the EQ in the app over time, basically increasing the bass by 4.5 dB and the treble by 2.5 dB to get even more dialed in to the sound I prefer. Now, the S2s offer an impressively wide soundstage with a level of detail and precision that I've never heard in any other pair of wireless headphones. The highs are clear and articulate, while the mids remain warm and rich, providing an incredibly immersive listening experience. I also appreciate that the S2s don't sacrifice bass response in pursuit of clarity; the low-end is powerful and well-defined, never overpowering or muddy. As a true audiophile, I can confidently say that the S2s deliver a level of Hi-Fi audio quality that is unmatched in the wireless headphone market.

"” BUILD QUALITY "”
When it comes to build quality, the S2s are simply outstanding. Crafted from a high-quality plastic that feels almost indistinguishable from aluminum or other light metals, the entire build of the headphones exudes a premium feel. The materials used make them lightweight yet durable, perfect for extended listening sessions without discomfort. The ear cups are plush and comfortable, providing excellent passive noise isolation. The S2s also boast a sleek and elegant design, making them as visually impressive as they are sonically.

"” BLUETOOTH & CORDED CONNECTION TECHNOLOGY "”
The S2s feature the latest Bluetooth technology, ensuring a stable and high-quality wireless connection. I've experienced no latency issues or connection drops, making for a seamless listening experience. The inclusion of a USB-C to 3.5mm cord and a USB-C to USB-C cord allows users to enjoy Hi-Res music quality, which is a fantastic addition for those who desire the best possible audio experience. I find that using the corded connection with the built-in DAC delivers superior sound quality compared to Bluetooth alone, especially when listening to lossless audio formats such as FLAC or TIDAL's Dolby Atmos tracks.

"” INCLUDED CASE "”
The Px7 S2s come with a fantastic case that is both functional and aesthetically pleasing. The case is smaller and less bulky than the XM5s, making it easier to carry around without taking up too much space. Made from a nice canvas-type material, the case feels durable and offers excellent protection for your headphones. The case is far superior to the AirPods Max's, which don't even come with a case, and it's clear that Bowers & Wilkins put thought into creating a case that is both protective and stylish.

"” NEW BOWERS & WILKINS APP "”
The Bowers & Wilkins music app is a fantastic addition to the Px7 S2 experience. The app enables you to adjust EQ settings, including treble and bass, allowing you to fine-tune your listening experience to your preferences. Additionally, the app integrates multiple streaming platforms like TIDAL, Spotify, and Soundcloud into one centralized music hub, making it easy to access and enjoy all your favorite music from a single location.

I particularly appreciate the ability to listen to TIDAL's Dolby Atmos songs in a standard FLAC format, which sounds much better to my ears. The app is user-friendly and responsive, and I find it to be a valuable tool in getting the most out of my Px7 S2s.

"” FINAL THOUGHTS "”
Ultimately, the Bowers & Wilkins Px7 S2 over-ear headphones have exceeded my expectations in every way. With unparalleled sound quality, exceptional build quality, versatile connection options, a fantastic case, and a highly functional app, the Px7 S2s have quickly become my go-to headphones for enjoying Hi-Fi audio at home. As an audiophile, I can confidently say that these headphones offer a listening experience that is unmatched in the wireless market. If you're seeking a truly premium audio experience, look no further than the Px7 S2s.

My old headphones finally died out. (JBL's) Been researching for quite some time to replace.
Looked at the Sony's, didn't care for the touch controls, I prefer buttons. Looked at and purchased the Bose's QC 45's. NC was top notch, sound quality was also very good. However, the build quality left a little to be desired. Not that they were bad, just didn't feel like high end headphones.
The Bowers & Wilkins checked all the boxes. Quality sound. The best of all the headphones I tested. Deep bass, clean midrange, crisp highs. Quality build. These felt like premium headphones should. Nice materials, very solid build. They are a little heavier, but I believe that is from the quality materials that were used. The NC is where they get a 4 star rating. Having used the Bose QC 45's I would say they have the better NC. Not that the B&W are bad, just that the Bose's are better in that department. Comfortability. I wear these for watching movies late at night. They are quite comfortable. 4 or 5 hour late night TV binges with no issues. Ears do start to sweat but I haven't found a pair of headphones that don't have that issue. Battery life is good as well. So far, anywhere from 25 to 30 hours of use time with ANC on. The B&W app is a little lacking, no EQ, unlike the Bose. So I will give that category to Bose as well.
Overall, I am very satisfied with my B&W Px7 S2 headphones. Would highly recommend.