I liked my Clinger Holster when I had a Shield. I actually own a Clinger Holster for my CZ 75D PCR. This is the third holster I've owned from Clinger. Another nice option is Hidden Hybrid.
The biggest thing that made a difference for me with concealing an IWB holster and comfort was pants and belt. I have Wrangler jeans with a little bit of a stretchy waist. My belt is a ratchet belt from Kore. Plenty of support, no sagging, lots of adjustment. Hope this helps!