I've got the 9 which is a bit smaller then the .45, but I've had no problems with carrying a full-sized in an IWB holster. I just layer a fleece as my cover-up. A Hawaiian type shirt will work as well in warmer weather, just avoid clingy fabrics like synthetics & make sure the shirt has a pattern on it. Patterns print less then solids.
yeah i use a sweat shirt or a really thick long sleeve fleece shirt. all i have is uncle mikes holster and i'm missing my old holster and i cant find it. i think it's stolen and i dont know who took it. I had the Cross breed IWB holster and that thing was awesome. But here's my problem. I'm a small framed guy who's 5'5 148 lbs. when i wore this holster and the .45 m&p i looked a bit more fatter/bulky. the handle/grip would stick out just a little bit but not too obvious. So, i'm going to wait till summer, once my classes are done and have more work lined up.. i'll go grab the compact version and a new holster for it. Maybe the 9 or 40.
i'll go look for some shirts / sweat shirts that has some patterns. for some reason i never thought about it and thank you! all i have is plain dark colored ones.