I bought a Creek Company pontoon boat from cabelas 4 or 5 years ago for around $299 or $350 (probably one step up on the food chain from yours). There are definitely spiffier rides out there, but for the money it has done just fine. My father in law (who has the same Creek Company pontoon boat) and I hiked into a lake an E. Washington lake and left our pontoons in his van, he didn't deflate his a little before heading out and the heat caused one of his pontoons to expand and rip out the cover. We e-mailed Creek Company and they sent a new pontoon, no questions asked, without us having to send in the old tube. Received it within a week.
I use it mostly on still water but it has done nicely on the Yakima etc. Great customer service from those folks even if you mess up your boat doing something foolish.
-JE