This is my first pair of MTB-specific shorts. I like the fit and the stretchy outer-short material ... definitely nicer than throwing board shorts over a liner. There's actually three zip vents and one zip pocket behind the right leg. The liner is well made and comfortable, but oddly, Pearl Izumi doesn't carry a comparable liner in their catalog if you want extras. I'll probably remove the plastic clips that fasten the liner to the shorts as they're unnecessary.