Love, love LOVE this MAC Pro Store! Every time we visit Vegas, I have to stop here and I always received great service. I will agree with other reviewers that it's usually busy in there and finding an artist to help is difficult but it was oddly slow when I visited last week. So I lucked out and got an artist all to myself! The Pro Artist helping me was awesome - helping me play with new colors and finding the right combos. They were out of one of the colors I really liked, but she helped me find an even better replacement.
The only downside, however, to this (or any) MAC store is that they always push the mascara at the end of the sale. I know it's part of the spiel, but it really gets on my nerves for some reason!
Regardless of the mascara issues, this is still an awesome store and I will definitely go back the next time I'm in Vegas!