How is the Cobra Fish'n Dive for a big guy? Like 6'7" 325lbs big. How does it compare to the WS Ride 135?

Seriously considering purchasing my first kayak but don't know where to start. My primary use for the kayak would be to shuttle me from one fishing hole to the next on the river, and maybe some fishing from the boat as I drift with the current. My challenge is my size...I am 6'7" and weigh 300 pounds plus. Stability is way more important to me than speed, especially since this is a river boat.

Is there a boat made for oversized dudes like me? What models do you recommend?

Am I crazy for thinking of taking it out on the river (i.e. American and Feather Rivers)?

Last question...can it be anchored in calmer water and fished from?

Thanks for any help.