I started IWB carry before Kydex was even a thing, so it was always leather for me. When Kydex really started taking off, I tried a couple of them, but always went back to leather. Kydex is too hard, causing too many pressure points as you move around, while leather, being soft. will flex and bend with your body, so no pressure points.
Two IWB holsters I have liked and carried with extensively are Milt Sparks, either their VM II or their Executive Carry, and El Paso Saddlery's C-Force line.
Get a good stiff belt designed for concealed carry holsters. I like Galco's SB series. Been using them for 30 years with no complaints.
^This.
But I haven't yet bothered to acquire a good IWB for the 365 yet. OWB on a Milt Sparks belt under an untucked shirt (or vest in winter) is GTG. I have yet to find a commercial kydex holster that I like.
