For concealed carry, it boils down to a lot of personal preference. How big or small are your hands? Do you like revolvers or semi-autos(sounds like semis)? Do you prefer single action(SA), double action(DA), or SA/DA?Is the gun going to be comfortable to wear for up to 8 hours at a time? What are your plans for summer when it's hot and you are likely wearing shorts and a T-shirt? Do you like to carry inside the waistband(IWB), ankle, belt, pocket, jacket, etc. How accurate are you with said gun? A well placed shot with a .22 does more damage than a miss with a .45.(But not by much). Are you trying to wound someone to get away or kill someone so they don't sue you later? The general rule is to carry the largest caliber you feel comfortable with. Do you live in an area where you will likely be up against someone packing also, where it could develop into a gunfight so ammo capacity is a consideration? Start answering questions like these for yourself and you will start really narrowing things down. I don't know if you're familiar with the 21 foot rule or not, but it simply states that when someone carrying a knife comes within 21 feet of you and you have a concealed pistol, you are pretty much dead before you can fully draw. We practiced this many times in my concealed weapons class, and the knife won every time. My point is to learn to shoot mainly at 20ft. or better since you are screwed otherwise. I personally now carry an EAA Witness Elite Match in 10MM, it is a 15+1 single action. Do some research on that round. It's very nasty (pretty much a .40 cal magnum). EAA makes a model called a P carry in 10MM. The nice thing about the Witness line, is that you can change calibers simply by swapping out the slide. They have conversion kits that are ~$200 each in the following calibers: 10MM, .45, .40, .38 super, .357 SIG(custom), 9MM, .380, and .22 LR. I also recommend looking into a thing called Clipdraw. It's like a knife clip for your gun. Mine weighs about 2-1/4 pounds, and the clipdraw holds it fine. I carry in a cargo pocket since I always wear either cargo pants or cargo shorts. The advantages are that you can reach it from a seated or standing position which is nice. It is also fairly subtle since the cargo pocket is naturally baggy anyways. I do recommend a pad between the gun and your knee or you'll be sorry.