AAEN Performance is a company that has been around for years. They are a Polaris specialty shop and their stuff is usually top notch. I haven't heard anything about their Predator pipe yet. From everthing I have read, a 5hp gain on the Predator is pretty good. Usuall the gains are down low where the Predator needs it. I'm waiting to see a pipe comparison before I spend the money for a pipe. The stock one flows pretty well at high RPMs. It just doesn't sound really cool like an aftermarket pipe. Hot Seat is another Polaris specialty shop that does good work.