Hey there. New to the forum here. Can't help you about the pistol, but what I can tell you is that I went to Vegas a couple weeks ago and wore my leatherman in a leather sheath the whole time (except while hitting the Playboy Club, quite swanky by the way). I even asked the front desk at our hotel/casino (the Palms) about their rules re: knives and even the manager had no clue and said do what you want. They suggested I contact the police if I was concerned.I didn't bother.
In a nutshell, I wore it all week in plain view, bars included,and not a word was said.
The only "no guns" sign I saw was at the (damn, forget the name of it) - Vegas' version of the space needle; they had the sign as well as a metal detector. I put the knife in the little tote and sent it around the outside of the detector, collected it on the other side and put it back on. No probs.
Have fun in Vegas.