I use the Alien IWB for my Kimber .45. I can use it with pretty much any pants or shorts without a belt so long as there is a drawstring (mainly for shorts). Really good holster. I print like crazy with that big ol’ gun when wearing athletic shorts, but I really don’t care.
I’m trying to dress a notch better lately when I go out in public, and it makes CC a little easier a lot of the time, but Summer will present a challenge. Baggy shorts and shirts make things easy. A comfy under the shirt shoulder holster would be great, but that’s something I would almost want to try on before buying.