I just recently purchused a 24" Nimbus 2 freestyle uni from Gary Land (www.unicycles.com). It is great to ride and extremly smooth. The frame is strong as so you can do street, trails and MUni as well. It will fit us to a 3" tyre so u can easily change it need be. It comes with a red or blue chromed rim with a matching seat. its chrome and has 48 14G spokes so it is strong and can take drops of up to 4-5ft. you can read more about it on www.unicycles.com. I have been using mine for at least 1-2 hours a day for the past 3 or so weeks and nothing ha come loose or screwed up in anyway. its a great uni for $300.
cheers, keep it wheel.