This is an important point that I missed in my post. I only use IWB holsters with reinforced mouths that stay open after the gun is removed. While some people ignorantly claim "I don't need to speed re-holster," it's not for that purpose. It makes for a safer, more fumble-free re-holster. It's easier to insert the gun without having to point the muzzle towards your body to wedge the mouth open, stick your fingers in the path of the muzzle to open it up, or remove the holster to insert the gun. It also facilitates practicing, by making more efficient use of time because you don't have to try and use one of the aforementioned methods to reholster in an unreinforced holster every single time.

Just my opinion.