Personally, I'm partial to Mernickle slide (loop) holsters. I've had several made for various weapons (XD .45, XD 9mm, Taurus 1911) and they work very well for me. I'm a big guy (too much belly) but find wearing the slide holster at 5 o'clock to be very comfortable for extended carry. An added bonus, for me at least, is that when the weapon is removed (say, at work, where I store it in my desk drawer), almost nobody recognizes the holster still on my belt; probably most think it to be a cell phone holder or something. This works for me as I have clients in and out all day and don't need to take up my time with extended conversations about carrying. My .02 cents.
At the risk of being accused of being hostile to SC LEO's, I would like to add that the M-60 crew-servered machine gun falls under NFA rules. For some reason when ever I mention NFA rules people somehow think it is hostile to SC LEO's. Also note if you live in SC, 23-31-310 through 23-31-370 describe additional restrictions put into place by the state of SC on NFA weapons.
The sixty gun has a rather storied history in various armed conflicts.
+1 on the CrossBreed for IWB.
I like the Desantis Gunhide holsters. I have the Speed scabbard for the revolver and a thumb-break version for the M&P45 both in black. Fit is good and break in time is quick.
Holsters are a very personnel thing. Gotta try a few and keep the ones that work.
Peace...
You can give peace a chance alright..
I'll seek cover in case it goes badly..