Hey Eyes! I've been carrying my 4" XD40 in a Crossbreed Supertuck for about a year now. The XD is a double stack with a wide grip and it hides real well in the Supertuck. I'm 5'9" 275 so I got that Dunlop thing going on and the rig is still comfortable to me so a slimmer person will most likely wear it more comfortably. Like it was said previously, a good belt is essential to the stability of the rig and to your comfort. A floppy belt will lead to a floppy rig.
Crossbreed was the pioneer but there are some more that have spring boarded off of Crossbreed and have made some innovations and improvements. I think you might want to check them out before you jump on on a particular brand.
Good luck with your decision.
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