The time has come to buy a Glock. I have two 45s an older Colt commander, a SA Range Officer, two 9 mms, Bereta 92F and a SA XDM a pair of 38 spls and a LCP. What I want to add is a 40 S&W to my stable. Thinking about about a Glock 22 or a 34 both Gen 4. My son has both of them and a 23 as a duty carry (he also has 45s and other 40s). The 34 Gen 4 he has shoots very well. His 22 is an older model that I shot some time back. He and his guns are in WA and I'm in AZ for the winter. I plan to take three or four hand defensive gun training classes and would like a 40 to shoot. The classes require 200 to 300 rounds to be fired. Does anyone have input on these two or maybe other Glocks to consider or is it wise to enter classes with a new gun?