The 300 is a sweet bike, you'll be happy with it. Honestly, I 've never had much trouble w either Green or Red sticker bikes, but I mostly enter local desert races. I'm sure some of the Offroad parks may be more strick.
FYI my friend bought a new GG 300 2 stroke and got a Green Sticker. Why? I don't know. He bought one and was surprised when a green sticker showed up.
If you really wan the trick set up, and are thinking four stroke. Buy a new KTM 4 stroke EXC. They come w a street plate. :cool: