All tests done by Glock aside...
Until someone can prove to me their M&P or XD can stand being thrown from an airplane at very low altitude onto rough/dry terrain, thrown onto concrete from the rooftop of a house, shot and hit with a .22 pistol, immersed in salt water overnight, completely filled with sugar sand, and all while loaded and firing when the trigger is pulled the first time, I'm sticking with Glock. Don't believe me, head to the GlockTalk.com forums. There's a subcompact Glock in my future for a carry gun, unless I find a gunsmith who can work on a Kahr (slim chance, it seems).
My family's G17 has been through some rough times too, and I haven't encountered a weapon more dependable weapon yet. Glocks are absolutely safe unless the trigger is pulled, and if you don't believe it then strip one down and take a peek. Seeing is believing.