If your looking for a hillshooter build, I don't think it matters its mostly just outlaw racing, or atleast around here in oregon. From my experiece, if your building a strictly hillshooter bike, one of my main focuses would be dropping weight and setup. You can make a 4 mil cub keep up with a lot of bigger motor bikes if it is set up right. Any one of the cub configerations are great. If it was me I would get a JJandA axle, a light swingarm and front end. some frame mods like chromoly subframe and possible stretching out the front. probably a 4, 7 or 10 cub on alky, out of frames and overide built right with lock out, straight cuts.... ect ec.t.. Oh ya, works or marvin shocks to drop some more weight and a good set of paddles like 22-11-8 superlites.... JMO.. But the list could be endless, depending on your pockets and what your really looking for. Good luck man and keep us in the loop!!