RE: best self denfense gun
Actually, most of our Spec. Ops. guys now carry the H&K Mk23 SOCOM pistol. It's also, interestingly enough, the first pistol classified by the military as an offensive weapon. All other pistols have always been considered defensive weapons. The SOCOM was designed to give spec. ops. guys a supressed alternate weapon when their larger weapon like the M-4 or shotgun is impractical or when stealth is necessary.
It's one pistol I wish I could own, but the price tag is a little rich for my blood.
There may be limited issues of other HK's in the U.S. inventory as well that I'm unaware of. Certain Marine Corps Force Recon & Scout/Sniper units also use custom 1911's still as well.
Mike