My back was broken in a car accident and sitting is uncomfortable for me. Without a seat I wouldn't be able to use any kayak.
This is the best kayak seat I've used so far. It fits my 12.5 foot Cobra sit-on-top perfectly and it adjusts easily. The cushion is just the right thickness although I wish it were a tad wider. I like it so well I bought one for each seat in both my kayaks (4).
Pros: it's lightweight, sturdy, looks good, comfy and keeps me in the kayak. Cons: it could be a little wider in the seat, thus the rating of 9 versus a perfect 10. I would have rated it 9.5 but that wasn't an option.
My experience is that this seat totally transformed my experience of paddling a sit-on-top (SOT) kayak. I normally paddle a high-performance, sit-in, sea kayak, and I dislike paddling SOTs and do not own one since they are so uncomfortable for me to paddle. For some reason, even when pushing hard on the heel stops built into a SOT, my butt slides forward when paddling the kayak, which results in an extreme reclining position so that I cannot use torso rotation, which is very painful to my lower back and extremely exhausting (I become exhausted partly from the pain). However, when I visited Lake Tahoe last summer a SOT was the only kind available to rent, but all of the SOTs had the Ocean Kayak Comfort Seat installed. I was dubious, but rented one anyway. What a transformation! While the 11-ft by 32-inch kayak itself was somewhat of a barge, and weathercocked badly, I stayed in place and could use my normal torso rotation, and did not get unnaturally exhausted. Although I do not own a SOT, I plan to buy a Comfort Seat to take along when I run into SOT kayak rentals. I cannot think of any reason not to rate this item a "10".