Have owned and fished from a Sevylor river xk1 Whitewater kayak for about ten years. Because its graded for extreme whitewater its probly tougher than many inflatables, no make that any kayak of any type, yeah you could stab it hard, but that'd bugger up most any kayak if you did it hard enough. Given that its designed to bounce off've big sharp rocks at high speed it has to be pretty resilient.
Never come close to puncturing it with a hook or knife, in fact I reckon you'd have to be trying pretty hard to do it. Folds up to about large backpack/mid size suitcase size and stores and travels easily.
It has self draining scuppers but if you leave the plugs in you'll only get a damp bum at worst. Great for getting into those hard to access places to launch and its very fishable. You can't really add rodholders etc, but its fine just hanging the rod over the side with a leg or strap to hold it in place.
The downsides (there always are compromises in any boat)
Relatively lightweight and high sided so wind can be an issue. Quiet calm waters no problems.
The rocker on this boat that makes it so manouverable, means that tracking can be a problem till you figure out how to paddle it properly. Once you do that it gets easy. For getting on the water its a breeze, but if you plan to paddle any long distances you had better be a fit and efficient paddler. 8) ( I used to be). I have a real kayak but still chuck the inflated one into my Yaris with seats folded down some times just for a quickie paddle.
Don't discount inflatables. They ain't the stuff yuppies would use 'cos it looks a bit like a big red banana, but they can be a very useful addition to anyone's fleet. Don't even think about getting a cheapie inflatable unless you're prepared to be way cautious.
Good luck.
Regards John.