EXC just for the bigger tank, when I used to go bush on my old old old old TT250 I would always have to cut it short because I kept getting close to empty, so bigger tank would be a major priority for me.
Matt I was also thinking about an RMX or a YZ but they seem to jump a bit in price even the early 90's models reach $2500, it should be a $1500 bike IMHO