Well I have now owned, 2 - 1911's, a Ruger SR9, 2 CZ's, a Glock, and have shot extensively, a Sig 226, and a Beretta M9.
Of all the above I always go back to that G17! The funny thing is at first, when I handled one in the store I hated the feel of it. Got to shoot one finally while at the range and was amazed how well it shot in my hand.
I have since got rid of all my pistols except my Nickel CZ75, and I think I am going to be trading her for a Glock again. Either G17 or maby try out a G19 this time.
As far as parts and durability goes, how may parts does your SIG have? Now how many on a Glock?
Besides a 1911 the Glock is going to have the most easily found and replaced parts of any gun on the market!
This is probably a big reason alot of military and law enforcement like them, and price helps alot to.