I would also have to say go with the Glock, however they are both a different type of animal. The P22 is more of a range / plinking gun as it is merely a .22, the Glock would be better for personal / home defense.
That aside, the P22 has had issues in the past with it's slide cracking. It wasn't made out of the normal steel as per most handguns, but instead a zinc alloy. I do not know if this has changed or not, but the second thread I've linked below is fairly recent, so you never know.
P22 Slide Breakage:
http://www.thefiringline.com/forums/showthread.php?t=172363
http://glocktalk.com/forums/archive/index.php/t-1019873.html
I also suggest you rent the Glock 26 (if you haven't already), as it's smaller size and lesser weight might make it a bit less controllable for some, which in that case you should try the Glock 19 which is a little bigger, but still easily concealable. Either way, you cannot go wrong with a Glock. I've had a lot of experience with them, especially the 17, and they are very easy work with and replace parts on.