Hello. I have a G17 and shoot it often, and as others have said it will handle +P and +P+ just fine. The NATO spec hardball has some nice kick and bang to it!
That said, I rarely ever shoot anything but standard pressure ammo and I usually carry standard pressure HP's for CCW. I just don't think a little extra velocity will make a whole lot of difference as long as you hit your target, at least not enought difference to justify the extra stress on the gun. To my mind, accurate follow-up shots are more important....but no matter what you shoot the G17 will gobble it up and ask for more.
Good luck, and good shooting.