I would like to request some input from you guys that run the 150SX in MX. I realy thinking hard about getting one for my 15 year old son. He runs supermini right now and I just broke him out on our RM125 a month ago. He has already run the 125 in schoolboy class and runs in the top 4 around our local area. He has just out grown the supermini at 5'6" 140lb. If you guys don't mind feeding me some input on how the 150 stands up to the thumpers off the starting line to the first corner and has anyone run the bike in the amature nationals? Any info would help, so don't hold back. I just hate to do the 4 stroker again.