The Shift is a no-frills sled in the Polaris lineup. The 600 is a GREAT powerplant, it has a lot of power and is very reliable. IMHO, the Shift is one of the better values in the Polaris lineup. If it's not beat to death and has been maintained, it should last you a long time!
2007 Dragon RMK 700 155", 2008 RMK 600 155", 95 Prowler 550 2-up, Really OLD AC Cheetah