First off, great choice in carry gun, that is exactly what I carry
Secondly, I have had a few IWB holsters. I got an Alien Gear 3.0 just a month ago and I really like it. Comfortable, adjustable, easy to holster, and seems well constructed. Biggest complaint initially was getting it clipped onto whatever pants i was wearing that day, but I got used to it. Still, a single clip design is more convenient to take on and off!
Personally, I wouldn't use IWB for IDPA. The reholstering of a hot (loaded chambered) into IWB is a little unnerving even after a few years of carry! While I don't compete, as I understand it there is a lot of in and out of the holster.