Ditto on the Feathercraft, the new Airline line is really well engineered. They're really stable and fast, at least the Java is. The Uno is a bit shorter and wider (2") probably not as fast but maybe a little more stable - only weighs 25 lbs.
Since there is a rigid subframe more of your body's energy goes into making the boat move forward, it's hard to believe it's an inflatable. It's also super comfortable.
Problem you might have is in figuring out how to rig it for fishing. I have one on order, after having tried it out, and will be working out rod holder, fish finder issues soon.
On the cheap I would check out the Innova's, they are deciptively good for the money. Probably due to the cost of cheap labor in that part of eastern europe. Still not comparable to the Feathercrafts, which are pretty expensive.
I have a Folbot Aleut (folding kayak) which I love (38 lbs, 12' x 32"), it's super stable and takes a sail but it's s-l-o-w like all really wide boats. There's a new, bigger single they make called the Yukon which seems to have a pretty huge ****pit and is almost the same weight. It looks like a good fishing yak for a folder.
I have two Stearns inflatable kayaks. They are very handy. They track fine, although they sit lower in the water than you might expect. If you're going to be going over a lot of rocky terrain at high speeds (like down a river), you might want a hard bottom.
I found it hard to fly fish from one; spinning is more do-able. Although if you get a treble hook lodged in the material in the front of the boat, you may need some help reaching it.
My kayaks store very nicely in my closet in a sq-foot-challeneged NYC apt. Also, I have a 20' Maritime boat, and they are stowable in the front compartment.
All in all, I think they have a niche. For the money, they are a good buy, and may enable you to peacefully get to some spots that are otherwise out of reach.