I picked up a well used but perfectly usable 15' Grumman Sport a few weeks ago. I bought it strictly to fish out of in local lakes and rivers, I harbor no illusions of actually paddling it.
Today my fiancee and I hit the lake with it. I must say I'm impressed. It moves very well with a 40# thrust trolling motor on the stern. It was quite windy today and the motor moved the boat easily. The only downside that I see to the boat is that the stern seating position is pretty short. That makes for an awkward reach around to run the trolling motor.