I have been carrying a Shield 40sw, but I just got a Shield 45acp. Looking for something for the new 45acp.I also have an MTAC. But once I went to Kydex, I never used the MTAC again. The best IWB holster is the one that's comfortable and safe. If it's not comfortable, you won't carry your gun. If it's not safe, you'll shoot your ass cheek. There's also a trade-off between comfort and ability to get to your gun. If the gun "disappears" on you and it's super comfortable, but when you need to draw it, you can't get to it...kinda defeats the purpose. I wear a custom Kydex IWB just in front of my hip around the 3 o'clock position. I know I can get to my gun because I've shot dozens of IDPA matches from this very holster. Probably has about 200 draws out of it between matches and practice. Depending on your gun, you may want something different. Some guys like a Glock 19 in the appendix position. Some guys like a LCP on the small of their back. All comes down to individual preference. Let me know what gun you have and I'll see If I have an IWB you can demo for a few weeks to see if you like it.