I've been very pleased so far with my Corbin. I have an earlier bike, so fitment was no problem. I've got probably around 700 miles on it now. At first it was very uncomfortable. Now it's more comfortable, but still feels like I'm sitting on a rock. The main thing, though, is that it doesn't give me that ache in the tailbone that I'd get after about 90 minutes on the stock seat.
As far as the in/on thing goes, the Corbin definitely has more of a pocket. It also seats me a bit further forward, so my legs are in a somewhat more comfortable position.
