I carry IWB, as its the most concealable way for me to carry and I also find it more comfortable.
For the most part, I gave up leather as soon as kydex arrived on the scene. For anyone who carrys every waking moment, sweats like a pig in the summer, and works physically outdoors, year round, its the ONLY way to go.
Leather just does not hold up to day in, day out hard use like kydex does.
A couple of the comments here baffle me.
Leather molds against your body.
No matter what you use, its the other way around.
If the Kydex is not molded to your body exactly where you are going to wear the holster, it will probably/possibly be uncomfortable.
See above.
I will never again holster an Eclipse or Black Stainless 1911 in a kydex rig, either due to the scratching.
Kydex doesnt scratch your gun. Anything you put your gun in WILL wear its finish. Leather is actually worse, since it tends to embed dirt and debris into it. You can wash your kydex holster out in the sink, dry it with a paper towel, and your right back in business. Kydex does not hold moisture, unlike leather, so your gun is not wet for days while you wait and hope it dries out before your gun starts to rust.
SQUEAK...SQUEAK...SQUEAK...what was that you were saying? What part of kydex is noisy? The draw? The reholster? My leather holsters, especially new ones, were VERY noisy, and they also had that nice leather smell that made anyone next to you think you were wearing a saddle.
I used to go through a couple of good leather holsters a year. The last couple were Galco Royal Guards. Summer is what usually killed them for me. They would get wet and stay wet. Rough out leather is the worst, as it sucks up sweat like a sponge. Once wet, they dont dry out overnight, and the next day, they are sucking up more. Before long, both you and your gun start to suffer. I used to rotate between two holsters during the summer to try and get them to dry out. It never worked to well, as the wet one would not dry over night, and the one you were using while you were waiting was wet the first day it was worn, so everything was in some degree of wet/damp all the time.
Speaking of suffer, how many here have spent the whole day at heavy labor in 95+, high humidity, with a wet leather holster rubbing against your bare skin, when your tee shirt rode up and you cant fix it? Take my word for it, it SUCKS, big time! Kydex isnt anywhere near as annoying, as it doesnt absorb the moisture, and slides across your wet skin. It also doesnt have tanning chemicals in it that tend to aggravate abraded skin.
Just to give you an idea of how well they wear, this Blade Tech IWB was used daily for about 10 years. In that time, all I had to do was replace a couple of straps. I did break off a small piece of the sweat guard. Its still as serviceable as the day I got it, and I still have it, although its been retired along with the 1911 that rode in it. The one on the right is the 10 year old holster, the one on the left, a new and unused back up.
This is a pic of the last Royal Guard I used. It was about a month or so old ( in late summer) here when I switched. It had been sitting in a box for about 10 years when the pic was taken. I sold it on EBay for about what I paid for it.
The duct tape was an attempt to slow down the sweat soaking in, didnt work to well.
Dont get me wrong here, I still use leather holsters on occasion, mostly in the winter. They do still have their uses. I like the Milt Sparks VMII's quite a bit. I also like the Galco Executive for my P230 and 642.
I know I'm probably an extreme case as far as how I carry and what I do and have to deal with to do it. I suppose if you arent as active, and in air conditioning all day, its really not to much of an issue. For flat out practicality and utility, kydex cant be beat. It wont win a beauty contest, but its beautiful to me, and I wont hesitate to slip any gun I carry into one.