Assuming that I'd just use my kydex belt holster for repeated drawing, why is it a problem that the Bianchi folds?
You don't want a holster that folds up because the need to re-holster a gun can be very important in any kind of emergency situation. You need to be able to draw AND reholster with one hand, without taking your eyes/attention off a person/animal/whatever got you to draw in the first place.
Second, as a safety issue, if your holster collapses you're pretty much going to have to get your support hand's fingers in there and hold it open so you can insert the muzzle of the gun -- which means you've got your fingers in front of the muzzle. And that's dumb. Or, you can do the wiggle and pry thing and try to use the muzzle of the gun to open the holster back up (against the tension of your belt). Now, though, you're not inserting the gun straight back into the holster -- you're sweeping your pelvis and legs while using the gun as a shoehorn. Also, very dumb.
Third, as a practical issue, if you holster your gun (lets say it's a nice fat XD, SIG, or maybe a Beretta 92) in a cheap flexy IWB holster and then cinch your belt tight to secure it...then draw the gun...and the holster collapses ... and your pants fall down...
A quality holster will be VERY hard to collapse. Many good IWBs even have a metal stiffening spline buried in the layers of leather so they won't let you down like this (though very well made holsters may not even need it). That's just the way good, professional quality gear is made.
And it's NOT the way the cheapy "leather sock" holsters are built. But that's why they're cheap.
My real concern with the leather holsters is that they'd be uncomfortable to wear with the big gun, since they offer no structure, and no protection between the grip and body. But maybe there's more to it.
A good leather holster is the exact opposite of what you've described. They are very substantial, offer rock-solid support, and will present a smooth(er), shielded side where they ride against your body.
-Sam
(P.S. -- I don't carry an XD, but I do carry both a 1911 and a 4" S&W 629 IWB-style fairly regularly. (No, not at the same time.) It just isn't that big a deal.)
