Sea Eagle has a pretty much no questions asked 30 day return policy. Pick one, see if you like it. For the same price (or less) you can buy a nice recreational sit on top kayak that's very stable and many are set up pretty well for fishing. I have a small 4-door sedan and I have cartoped my 12 foot Hobie Outback Mirage (the pedal drive). I love my pedal drive by the way, it's fantastic.
I purchased one of Sea Eagle's small boats (not the yak) set up with the floor and motor mount. I was really impressed with the quality and felt safe mucking around the little lake I used it at. I had difficulty with it because of the size of the air chambers made it hard to get in and out without geting dunked. I wound up returning it because it was just to big and heavy to handle very easily. Didn't have any problems with Sea Eagle when I decided to return it, got a full refund with no problem.