It is difficult to emphasize how important a good holster is to carrying and using a handgun. There are two areas in which to consider, open carry holsters for duty use and holster designed to be used when the handgun will be concealed. There is a simple rule to buying holsters - CHEAP WILL NOT CUT IT. Of all the various shooting junk I've accumulated, I have a huge selection of holsters. I have never paid less than $50 for a good holster - if you pay anything less you will regret it.
In my mind, I only rate the NSA as "adequate." The point where the belt secures the holster is far to the rear, allowing the weapon to shift excessively. Also, it is a pain to adjust the holster for different belt sizes, requiring you to remove the belt loop - using a screwdriver - and replace it with another of the appropriate size. The NSA works but if I ever buy another leather inside the waistband holster, I'm going to look at something like a Summer Special - they are expensive but I've never heard anything bad about them.
I use two holsters for concealed carry, a Galco NSA for inside the waistband carry, and a BladeTech Belt holster for normal belt carry. I don't use the Galco very often and only when the particular clothing I'm wearing requires it - typically a polo shirt or similar open bottom design.

