I carry a M&P 40FS. I use a Galco King Tuck IWB holster. It's ok if I wear a very baggy shirt or a thick sweat shirt. Not to bad in the colder months, but does not work for me in the warmer months. IWB all day carry also gives me back pain after about half a day of carrying. But thats just me. What sux for me may be the greatest thing to the next person... We are all different. As for me, I'm thinking of getting a 40c to carry in my cargo shorts for the summer time. (May just be a good excuse to by another M&P!)