1. I would not be confused by personal, limited opinions nor vast experiences from gun store sellers. 2. I would not be limited to Glock 3. I would be attracted to a caliber & recoil & conceal ability more than a brand, most of which excel in some of these priorities and never others in their focus to compete in the marketplace 4. I would spend a lot of time on Genitron.com doing research AFTER renting enough range guns to KNOW what level of recoil limits my ability to always make bullseyes 5. Chuck Hawks and LuckyGunner.com Labs will help you with Stopping Power calibers to consider 6. THEN when confused over a few remaining choices, before making a $600-1200 mistake, see if Hickock45 has a video on it - he's a down to earth non-salesman that picks through firearms giving you an up close feel for each Glock has too much superior competition these days in most calibers.