We have a small Hyundai ioniq PHEV, but we have 2 toddlers, an e-bike, an e-trike and tons of toddler and beach accessories and clothes we wanted to take on a 7-hour journey for a 7 day stay. We contemplated renting an SUV, shipping some stuff, buying a bigger car, getting a u-haul, etc. We ended up getting this roof top carrier, a trailer hitch and a hitch cargo carrier instead, and we actually had room to spare. Our friends laughed that it would be impossible in our car, but we did it!

This carrier takes up a tiny footprint when stored in its bag, enough that you could reasonably have it always stored in your car for whenever you need it. But its total volume when deployed is astounding. We put a pack-n-play, a bike trailer, 3 beach chairs, a beach tent, a baby gate, a child bike seat, 2 bags of clothes, a bag of beach toys, 5 towels, 4 bike helmets a bag of board games and 2 foldable strollers up there and we STILL had extra space. We don't have a roof rack so we attached the straps to the door frames with the included strap "adapters" and it was impressively sturdy. We never had a single problem. No sounds, no movement, no leaks, nothing. Only issue we had at first was we let the straps dangle inside the car window, and when it started raining hard it leaked into the car through the straps. Easy solution was to tie the ends outside, problem solved. The straps do not interfere with the door operation in any way.

The only downside to this, that I found, is that it reduced our fuel efficiency. That's kind of expected. I'd estimate this probably reduced us by about 15%-20% for fuel efficiency with another 10%-15% coming from our cargo/trike setup. With about 15 hours of travel time this meant 3 tanks of gas vs the typical 2, or about another $40.

All told, between the hitch, hitch carrier, this cartop carrier, the extra gas and some straps we spent an extra $425 to get everything we needed down to beach. The cheapest weeklong SUV rentals were $1000 and wouldn't even have carried this much. And the best thing is that all of this (except the extra gas) was 1 time costs! Next time we need to travel like this we can do it again for free!

Love it!

We wanted extra storage capacity for a long family trip in our 3-row vehicle with a built-in crossbar (two horizontal bars going across the width of the vehicle). the roof bag worked well and was spacious, but be mindful that it's going to take a while to put your luggage on your car roof particularly if you have a taller vehicle. the hooks for the crossbars are adjustable, but since you don't know how much slack you'll need for the amount of luggage you're going to put into the roof bag once it's on top of the roof, you're going to have to do some adjusting of the hooks as you figure out how to optimally pack your roof bag to maximize spacing. We opted to hook each corner loosely to the cross-bars and then add suitcases and bags on both sides of the SUV, which requires walking around the vehicle and reaching up high to make adjustments. Depending on the positioning of the cross-bars, you have to decide if you're going to put your hard suitcases in front of behind the crossbars. During the first leg of our 10 hour road trip, we noticed that we didn't secure the loose straps and they were flapping in the wind and rain the whole time. I tried to do a better job of securing the excess straps, but by the time we finished the 30 hours of drive-time, the edge of one of the straps started fraying. The 15-30 minutes it takes to pack the roof bag is probably more specific to roof bags generally rather than this product specifically. The plastic material and the zippers were sturdy. It rained for large portions of the trip, but the zipper guards did a good job of keeping the rain out and the luggage dry. I recommend this product, but would love a better way of securing the excess straps other than poorly tying a bunch of knots that I then had to undo later to get our materials. Also, be mindful of which luggage you may have to access and where you position them if you're planning on staying somewhere overnight during your trip. It's less fun to be rummaging around the different sections of your roof bag at night at the end of a 14 hr day.

UPDATE:
Three months of driving around the country and this bag held up great! We went through some crazy rain storms, drove 90mph on the highway, and generally put this bag through some hell and it got through it all.

A few notes.
1) The anti-slip mat is pretty worthless. It kept sliding back and getting all bunched up within the first couple days of use. That being said, we scrapped it and then never had any issues with the bag sliding around with just the straps.
2) Our stuff did get wet. It's hard to say for sure that no water ever got through the bag, but I do believe most of the water came from things we put in it while still wet. DON"T PUT YOUR WET TENT IN THE BAG! Or if you do, be sure to dry it out later and dry the whole bag. Wet things in the bag + sun = condensation on EVERYTHING in the bag.
3) Despite having roof racks, we ended up needing to use the door hooks for the front straps. They ended up scratching some of the paint off the car around the window frame. Not a huge deal, but for some people it would be a bummer. Maybe add some sort of anti-scratch material to avoid this (perhaps cut off a piece of the useless anti-slip mat?)

Overall, would highly recommend this product. For around $100 it gave us the extra space we needed for a multi-month road trip and survived lots of rain, wind, and occasional freezing temps.
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Original Review:
We're planning to take this roof bag on a two month road trip around the US. We've been loading it up and driving around locally for the past few days and it's been better than expected! No buffeting noise on the highway, the bag has stayed locked in place thanks to the non slip mat, and it actually looks pretty decent now that it's getting full. (Kinda floppy and unattractive when underfilled).

It got a thorough test last night with over 3" of rain and strong wind gusts right off the ocean. Happy to report there was no leakage and everything inside was completely dry this morning.

One minor complaint is that we had to use the door hooks for the front attachments despite having built in roof racks on my Subaru Outback. More of a complaint for the car and not a big deal, but worth noting.

The storage space is awesome. We have it loaded up with two large (empty) backpacking packs, a two person tent, sleeping pad, 8x8 popup tent, two REI flexlite chairs, a 4' folding table, and our climbing rope and gear bag. Might be able to squeeze a little more in, but already very happy with how much space it has freed up in the trunk and backs seat.

First use was very simple after I figured out how to attach under weather stripping, no luggage rack on top of van. Loaded 5 beach chairs, boogie board, dog stroller, beach wagon, towels, beach gear into this thing. Anchored down and it worked like a charm, even through rain and driving 80+ mph. Took it a bit slower initially and after first stop, saw that the straps didn't move at all. Sounds and drag are a bit unnerving at first when driving but this thing is great. Very sturdy but since soft case, you can really make things fit. Zipper is rugged and protected which kept everything dry. When parked we took off van and kept in hotel closet. If you have a higher vehicle, it can be challenging to pack and repack without help. Would suggest to anyone.

I am actually decently surprised by this bag. I just returned after a 2600 mile road trip with my family from Seattle to Southern California and back. Overall I am satisfied with this product. I got the 15 cubic feet model and strapped it to our 2012 Prius V and it was more than enough space for all our camping gear, pillows, blankets, and eventually dirty clothes bags.

Durability:
Only issue here was when we left to head back home, I noticed a few holes in the underside of the bag. I didn't store anything sharp in it so I am at a loss how they got there. Could have been giant desert spiders or my sister's dog. Either way, it made me think this bag is probably a one time use type thing.

Weather resistance:
I can't really speak to the water/weather resistance as we encountered virtually no rain during this trip except for a brief morning shower at my sister's house in the desert. Everything was dry inside after the rain.

Straps:
I read other reviews that said the straps needed to be tightened every hour or so at the beginning, but this was not my experience. I never felt the need to pull over and check the straps, other than at pit stops. The straps held up even though I averaged 70 mph, with a maximum speed of 80 mph for a few brief stretches. The only notable issue with the straps was after driving through a heavy side wind for about 60 miles, the straps on the side that got hit the most seemed a bit looser. Other than that, no issues with the straps. I really dislike how the hooks go under the weather stripping, which causes an annoying sound as you drive.

MPG:
I noticed this bag produced significant drag, reducing my average MPG from the expected 40 to 34 by the end of the trip. I've done big trips in this Prius before and the MPG has at most reduced to 38 when there's a lot of mountain passes/inclines. So it definitely had a major negative effect on the MPG.

Security:
The little lock that came with the bag (which would stop no one determined to get your stuff) broke instantly when I tried to set a new code, so that was out of the picture. All a thief would need to do is drive up with a pickup truck, quickly cut the straps and shove the bag in his/her truck to get your stuff. It is not very secure. One of the motels we stayed at seemed to be in a not great area so I opted to take the bag off the car and keep it in the room with us. I felt safer with it at other, nicer hotels which had lighting and cameras in the lots.

Overall quality:
I am impressed with this bag considering it was $60. It did the trick. However the major thing this product did for me was make me decide to the bite the bullet and get a roof rack and a large hard shell cargo carrier so the air can at least travel underneath it, reducing drag. Hard shells also seem to be way more secure.