I've dry fired my Glock hundreds of times practicing trigger control, with no sign or wear at all. I started using snap-caps, but because the striker must be pre-cocked by at least partially cycling the slide to the rear the snap caps were a PITA. If I accidently moved the slide back too far the snapcap would fall out of the magazine well or get caught between the slide face and the breech. Too much hassel, so I just dry fire without now.

I remember reading an atricle about competitive pistol shooting (either IDPA or IPSC, can't remember) that said that it's recommended that one dry fire at least one to two times as many rounds as they fire live rounds so that trigger control is second nature. It makes sense to me, so I do dry fire practice a lot with my pistol.

Mike