Currently wear an Aliengear cloak tuck... 3.5, I think? Anyhow, it's quite comfortable standing, but took a good deal of fiddling to find the sweet spot for sitting. Little bulkier than, say, an unreinforced leather would be, but still conceals well tucked.
When I was carrying OWB with an open front shirt, I was always paranoid about the wind billowing it open. With a stainless gun against a black shirt, especially, was a recipe for the accidental reveal. Now, can look neat with shirt tucked, and don't have to worry, it's not going anywhere.