I have something I need to get off my chest on the topic of holsters: I hate floppy holsters. I especially hate floppy inside-the-waistband holsters.
A holster needs to be at least semi-rigid, or have some reinforcement around the mouth of the holster, so that it will remain open and gun-shaped even while the gun is not in it. This is important so that the gun can be re-holstered one-handed.
You need to be able to re-holster the gun one-handed. This is not for any special ninjy reasons, but for safety. If you have to hold the holster open with one hand while you try and put the gun away with the other, there's practically no way to do it without pointing your gat at your own hand, especially if you're in a hurry or flustered, like you've just gotten off the phone with 911, say.
Even worse are the people I've seen who kinda force their flattened holster open by pressing the muzzle of their pistol sort of diagonally into their own love handle before wriggling the gun down into the holster. Imagine how that would play out: The bad guy's run off, the sirens are getting closer, the 911 operator tells you to put the gun away, and *BAM!* you shoot yourself right through both kidneys. That's a pretty serious social faux pas, right there.
The only safe way to re-holster using one of these things is to remove the holster itself from your waistband, get it onto the gun without pointing the pistol at yourself in the process, and then stuff the whole assemblage back where it belongs. Or you could, you know, just get yourself a holster that lets you put the gun away without endangering yourself.