Not to be too much of a smartass I did post this in a NC forum. . .I'm stationed in MD I live in NC
Then please disregard the first paragraph of my previous post....
NC is pretty OC-friendly, and as long as you know the "prohibited places" like restaurants that serve alcohol and places that charge admission (movie theaters, etc), you should be good to go.
There is no law about the kind of holster you must use. Wear what you are comfortable and familiar with. I prefer a retention holster of some sort for OC, and I have trained with the Serpa with my 1911 and my Glock, so I feel very comfortable with it and have a lot of confidence in that platform.
Some folks prefer leather with a thumb strap.
Wear the holster that:
1) you trust,
2) is comfortable,
3) is safe and secure,
4) fits your gun correctly, and
5) you like the looks of...
Since you are military (Navy or Marines, I assume) you are probably already familiar with the Serpa Duty Holster which has the Level 3 hood system. They are bulky, slow to draw, and ugly, Don't judge the other Serpas by the Level 3 Duty Holsters. The level 2 Serpa CQC is one of the most secure, fast, comfy, rugged, and good-looking holsters for OC out there, in my opinion.
I have uses Serpa CQC's for daily carry of a Glock 36 and a Para Ordnance P-14.45 for over three years and I trust them implicitly. I also use my Serpa/Para rig for USPSA competition, and it has performed flawlessly in that high-pressure environment, which involved running, banging into barriers, and rolling around on the ground.
But if you prefer leather, then there are plenty of great brands out there, depending on the specific firearm you are carrying.
If you feel comfortable with a "friction retention" holster (leather or kydex) then wear it.
Personally, I prefer some sort of mechanical retention like the Serpa, or a thumb snap (like on my Bianchi Special Agent, or some of the Galcos I own). The only time I wear a holster with "friction retention" is when I CC--I have a Galco SSS for the Para and a Galco IWB holster for the Glock and neither of them have any sort of mechanical retention--but if the BG can't see it, he can't grab it, right? ;-)
It's YOUR gun, it's YOUR decision.
But no matter what you end up going with, you need to practice with it, so you have the retention system down as a reflex that you don't have to think about to manipulate safely, quickly, and effectively.
Good luck, and Carry On!