I had the exact opposite problem... my lower jaw grew down and back, causing severe overbite. It also meant that the only teeth of mine that could make contact were my absolute back pair of molars, which were slowly grinding themselves into oblivion. The terminal result would be that the joints in my jaw would destroy themselves from having to move my jaw in unnatural ways in order to be able to eat.
Recovery was a huge annoyance... five weeks of a completely liquid diet, then another two weeks of soft food (defined as food you can eat merely by mashing it against the roof of the mouth with the tongue, since chewing was not yet allowed). I do not know if I will EVER eat yogurt or tomato soup ever again. In addition i have to have braces for approximately six to eight months after surgery, and had to have them put on six weeks prior to surgery.
Overall, I'd have to say I'm quite dissatisfied with the experience. Yes, the supposed problems with the joints are now resolved, but the surgeon was not able to line properly align the upper and lower jaw. The consequence is that the upper jaw is a few millimeters too far to the right and my front teeth don't line up properly. Symmetry is a big deal to me and it's been a major annoyance that I can't stop thinking about. The orthodontist is about to give up and take off the braces since he doesn't feel he will be able to sufficient correct the problem. This surgery was performed by supposedly the best guy in the western United States (performs about five instances of this procedure per week, over 15,000 over the course of his career).
If you have any questions about my experience, feel free to send me a PM. Hopefully yours will go better than mine.