IF these gloves continue to work and wear as well as they have for the three-plus weeks I've had them, I'd say that they are worth the $100+ price tag. But that's a big, fat IF.
Size: my hand measured approx. 8.1 inches, but I went with size XS/S, and I'm glad I did"”they're pretty snug while pulling the narrow area at the wrist over my hand, but otherwise are a perfect fit. I think the next size up, the M/L, would have been too big. I am tormented with persistently cold hands due to peripheral neuropathy, so I was looking for heated gloves (liners) mainly for indoor use like working at the computer, or just watching television. The main criterion was finding gloves that would allow me to type on a tablet keyboard. I'm wearing them now as I type this review, and they work as I had hoped. They cling pretty well to my fingers, allowing dexterity and avoiding clumsy fat-fingering of the keys that results from having sloppy oversized gloves hanging off one's fingertips.
For outdoors I just slip a pair of unlined leather driving gloves over them and am good to go"”they make a big difference.
A couple of little nits to pick: I wish they had located the battery on the back of the wrist"”as it is the bulk of the battery is right where one's wrists lay on the desktop while typing, which interferes with the ergonomics of convenient hand placement. And man are the LED indicator lights BRIGHT. Had to cover those suckers with electrical tape.
In short, these heated liners work as advertised, and I believe are a decent value. They have proved a workable solution to my longstanding problem of cold hands"”provided they pass the test of time...

I planned on using these gloves in extremely cold temperatures, as low as 0-10° F and wind chills to -20°. As of now, I have used them to temps of about 10°, with wind chills to -2°. I work in the Midwest, near the lakefront, and at heights of about 50 ft, meaning I'm usually very much exposed to the elements. On top of that, I am usually handling cold liquids, typically around 32° in the winter, sometimes colder.

I wear the gloves closest to my skin. Then I cover them with a light fire resistant liner. Lastly, I put on a pair of nitrile gloves. I have used them at least 15 times over the past 3 weeks and they have not failed me yet. While they do not keep my hands sweaty, they more than easily keep them warm enough to work.
All I needed was to keep my hands able to function at these conditions for up to 60-90 mins. These work perfectly.
I have yet to have the batteries die on me mid job. I charge them after each one for an hour or so and haven't had any issues.

The gloves do run big. I measured my hands as the instructions say and I was on the border of L and XL. So I got the L and they are a little big on me. Not too big that I can't use them, but definitely bigger than I was expecting.

The batteries are a bit bulky. They cause to cuff to be a bit large and cumbersome. I usually have to put the gloves on first then, then my jacket. The gloves themselves are thin enough though, even with the added layers, that I can even tie my shoes.

The only con I can think of is that they are probably a little difficult to clean. While I haven't tried because frankly I don't want to ruin them, I'm concerned that they either won't clean well or that I will damage them.

I love these gloves. I should have purchased them long ago. They are well made, durable, and function perfectly as described. I am a horse rider and these gloves allow me to enjoy my sport on cold days. I can even tack my horse with the gloves on which requires pushing small leather straps into holders. I have had to take off other gloves to do this. I can ride in these gloves and they are holding up great. The reins are rough and I worried the gloves would get holes, but they have held up great. The temp. settings are perfect. Slipping my hands into these gloves is like a warm cup of tea when you are cold. I am grateful to have found this product. I will be giving several pairs for Christmas this year.

UPDATE (original review below this part)
I got the Small which is actually labeled xs/s inside the gloves. Because they are liners, I'd still prefer them to be a tad smaller but they fit my female hands much better than the m/l. I actually started typing this review with one of them on. I can feel the wire that runs around the finger portion but it seems to be just one wire with more winding around the hand portion. I can't say my hand is really warm which I'd kind of expect since I'm sitting inside. I tried these while cross country skiing yesterday - it was in the teens but windchill at 0 or below. I wore these liners inside my regular heated gloves (which are a little too big on me - men's L). These liners fit underneath but more snug than the normal glove liners I typically wear. It might seem overkill to wear both heated gloves but I've been so miserable in the past I just want warm fingers! So, my face hurt from the windchill because it's hard to cover up completely and still see through foggy glasses, but my hands and fingers...WARM! So happy. Even with the slightly added bulk of 2 battery heated gloves, I was able to grasp my poles just fine and not have to continually stop to shake life back into my fingers. It is what it is - I need all this to be able to enjoy skiing. Oh, some review mentioned that replacement batteries aren't available. They are - right here on amazon. Search for the type of battery mentioned in the product description. Hopefully, though they last a decent amount of time.
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Ok, so I ordered the Medium which is actually a M/L. That's a big deal for a glove that is designed for men & women. It's fits like a large on my female hand which probably is more like a M/L WOMAN'S size - not man's. Part of the reason I got what I thought was just a M was that I think I straddle that size and it also had free returns where the Small did not. So, I know I need the small. I tested the glove first to make sure it worked, though, before buying the Small with no free returns. Each finger warmed up - almost immediately after turning it on. That's exactly what I need. So if the small will end up hugging my fingers, I think I'm set. However, the wrist where the battery is located is kind of bulky and may combat with my gloves that also have the longer wrist coverage (and battery! But that glove doesn't included the fingers for heating - worthless for me). If these work well, though, I might even be able to use the other gloves without the battery and rely on this liner. The cloth is soft and velcro easily adjustable. The button requires holding for a few second to turn off/on so this will be helpful to prevent accidental changes. I always wear a liner anyway so this may be an overall better solution for me. I often take off my over glove to wipe my nose which gets my hand colder even quicker. This may prevent that, too. My other battery gloves cost a little more so this price, if it truly works as it appears to, is worth it. I suffer from reynauds, poor circulation and even have had to quit X country skiing on days where the temp was in the 20s because my fingers simply started to get numb from gripping the poles. SO FRUSTRATING! This also happens on snowmobiles from spreading my hand out to grip the handle or press the gas - even with heated grips and my battery gloves! Having my fingers heated is what i've needed. I'll update after I get my size Small (which is suddenly also available with free returns but is going to take a few extra days).

I wore these or another pair of really thick heated gloves all winter. These were perfect for the average cold days, mainly wore to walk the dog, and would often still keep my hands in my pockets. They fit inside mittens but putting them in my normal gloves was impossible. They are liners but you have to size up your regular gloves to fit these inside. I have pretty bad Reynaud's though, so these are a life saver. Battery life is short but it suited my needs. Probably recharged every other wear so I may have gotten an hour of total wear between charges (30 min per day). I recharged more often though because there were several times when I forgot and it died on me mid-walk. I keep a spare pair of the disposable hand warmers on me just in case, but I'd rather avoid that if possible. Also - the battery pack on the wrists made it difficult to get my arm in and out of certain coats. Maybe men wouldn't have as much issue but for ladies clothing that is a but more tailored, I had to remember to put the coat on first and then the gloves. Minor but was still pretty annoying some days.