First off, pardon if bits of this are a repost. I didn't find anything specifically relating to this topic, though, with the volume of info on the forums, I've probably overlooked it.

First off, how prevalent is the usage of sidearms in actual combat. I realized that there are several roles that are issued sidearms and I've heard that just about anyone "down range" may be issued a sidearm. How common is it to draw a pistol in combat? Are there situations where combat personnel might forgo using a full-size battle rifle (such as CQB) in favor of a pistol? For the sake of argument, I'm speaking of the M9 and US personnel.

My second question pertains to tactical holsters. Younger troops seem fascinated with bits like this:


Are they really particularly useful in combat? My guess would be that it's more of a youthful desire for the "high speed, low drag" look. I can see how it would be more comfortable than wearing a normal belt holster especially considering how much other web gear is hanging about.

Given the amount of other gear carried on the belt, body armor etc. The drop leg holsters give (me anyway) better access to the sidearm. And the issue holster leaves alot to be desired IMO.