So far, my Gen 4 Glock 17.
I like the gun, though, so I suppose that means I've been pretty fortunate in my handgun buying. However, I still find myself wanting to take a number of other guns to the range before the Glock. I take it along anyway, hoping that it will really start to grow on me.
I have no real functional complaints about the gun. It stovepiped twice with the original spring, but it's had no problems with the "02" spring. It's not as accurate as my other semi-autos or other semi-autos I've shot, but expect that in a gun built with tolerances that allow it to shoot reliably after being submerged in sand, mud, and whatever else.
Mainly, for me the gun is pretty close to soulless. That doesn't mean I wish I didn't own it. It just means I'm not that excited to shoot it. I do appreciate its capabilities, though. If I ever had to survive outdoors in adverse conditions and could only have one handgun, it would very probably be some model of Glock.