I carry in this full Kydex IWB holster from FRONT LINE. I love it.
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When I'm wearing a T-shirt I just wear an undershirt underneath and that's enough to keep from printing.
Most days I just wear a shirt untucked and I'm good to go.
The full KYDEX gives me a very confident draw and reholster. It's smooth and retention screws are adjustable. I haven't had the slightest concern with retention.
The cool thing is that it's also tuckable. A couple of times I've gone full tuck with my shirt and carried right in front of people. They of course didn't notice a thing.
Oh, by the way, it shipped from Israel. The Israelis know a thing or two about self defense, so that added to the attractiveness to me. Said it was going to take 4+ weeks to get here. It didn't. I had it in like a week and a half. I'd buy another one tomorrow.