I went the .40 route with my Glock. I was a little apprehensive about the popularity of the round but its become almost as common as .38 Sp. I have a 6 inch blue Python I got in 1970. Its in 95 percent condition. I have pretty much retired it in favor of the semi auto.
If you can live with factory loads, then the Glock is probably the most reliable handgun one can carry.
I have a 17 and a 26, and have pretty much standardized on the 9mm for daily carry.