I'm pretty new to kayaking and I'm looking at buying my first used boat. The one I have in mind right now is a Riot Booster 50. I won't be doing a lot of river running at first but I know after a year or so I'll be going all the time. My biggest concern is if this boat is to small. I'll want to be able to river run it and use it as a play boat as well. I'm 5'10 and about 165-170. The max recommended weight on the boat is 181, anyone have any thoughts on if that is too close?

I don't think so. As long as you won't do WW V+ (what I don't expect as a "fresh" kayaker) I think you're oke.

I would say as long as you don't go over the recommendations then you will be fine. More important is to check out if you fit into the boat with the seat in the correct position (normally not all the way back) so that the boat is trim (level in the water). If you have long legs or big feet (or both) then this is sometimes much more of a problem with playboats.

Having one boat to play and to run whitewater will always be a compromise as being near the upper end weight wise is better for play boating and being at the lower end is better for running whitewater.

As bartw says below grade 5 you should be ok and I think the booster is a good boat to learn in.

Hope this helps,

Neil