I wear a 33x32 pant size... and bought the medium. DANG, they are baggy. Still functional though. I love them because they're water proof as all get out, tough (been crashing through a few trees and no damage so far) fit nicely, and the vents work great!
Other than the being a bit too baggy I would give them 5 stars.
I think these will last me a long long time. :)