It comes down to using what you feel okay with. While a 1911 or full sized Glock are great for uniform carry witha Sam Brown belt, they stink for just sticking in your pocket for a trip to town. There haeven't been pockets that big since Captain Kangaroo came along. If a 22 suits you, fine. If you want a 25, 32, 38/9, 40/10, 44 or 45, go for it. What LE does is often as much the result of bean counters or political whim as any real world need. (For instance, I'm amazed any police agency leaves range brass on the ground. It's worth $$$ ya know!) I doubt any major production caliber is going to go the way of 9mm Federal or 5mm Velo Dog.