[gigglesnirt]

a few will upgrade to shifter karts but you really could stay in rotax the entire time and be completly happy with it, it really depends on whether your competitive in competition or not, if you do well in rotax, keep going a few years you could always move up to shifter. on open track days rotax will make you feel good when your able to chase down the shifter karts who are supposed to be faster then you.