Couldn't be happier with this pannier. I must have looked at more than a dozen or so panniers and I purchased three different ones, ultimately settling on this one. It has all of the key features in a quality pannier - waterproof, hooks and loops on the outside for attaching additional gear, compression straps, clip at the bottom of the bag to hold onto the rack, etc. It looks great too, both on the bike and as a shoulder bag.
It's got the perfect amount of room to handle my daily commute - room for shoes, shirt, pants, and a few extra top layers that I may or may not need for the ride back. Doesn't wobble at all on my Topeak rack; fits snug and goes on and off in seconds.