The 40 S&W is a great caliber; plenty of power and chambered in some pretty compact arms. If I were starting out, that's the caliber I'd have. But it arrived a little too late for me. I currently have 10 pistols in 45 ACP; a 50 cal ammo box full of ammo, plus ammo stacked up in the gun room. There's another 50 cal ammo box full of 45 empties. I have a carbide die set with a taper crimper, 2 four cavity bullet moulds, one a 180 gr SWC, the other a 230 gr RN, and puddles of loading data going back to 1964. The situation is the same for 9mm P, except I have 12 guns in that caliber, and loading data from 1960. I really don't want to get started with another caliber right in the middle of these two. My sole concession to the 40 caliber is a S&W Highway Patrolman I had Bowen Classic Arms ream out to 38-40. Anyone else feel the same regarding these three calibers or any others?