Im about to buy a new sport quad and already have a 400ex, was wondering about how the polaris predetor 500 was as far as durability and performance?? The local dealership is running a really good special on the 08's remainning on the show room floor.  

I dont personally have one but three guys i ride with do an they love them.  these guys thrash quads and all they've had to replace is tires and oil.  

careful polaris has tons of recalls and defects.

you can view the many recalls and defects on the polaris machines at this link
http://www.atvsafety.gov/atvrecalls.html

buy what you like but personally i would push a yamaha before i rode a polaris.

if you go to the link i provided you'll see that the defects with polaris are not normal defects but are dangerous and have already caused serious injuries to the riders.

things like Steering stems breaking while riding.      
 Brake calipers falling off,
Ecm's overheating and causing fires that burned houses down if parked in the garage.
Oil lines that leaked and caused serious burns to the rider from hot oil.
Transmissions that locked up while riding causing the rear wheels to lock up.

and these aren't one time events the defects occurred in later year models after Polaris had to issue the recalls.

and polaris has recalls on the 08 models too, and some of them are the same defects that they have had year after year