Has anyone heard of or seen any of these ladies. I know that one of them is based out of Las Vegas. Is this another agency scam or what?

Really hard to tell--there's a few known, multiple-reviewed Twin City gals on there, ones that were around well before the site showed up.  That adds credibility.  At least one or two that certainly are not TC based, and that subtracts credibility.

The usual scam is to include just enough (2-3) recognizable locals that the page appears to be for real, and then pad it with 8-9 more hotties that never seem to be available when you call.  It's not that you get ripped off, you're just never able to schedule anybody but the 2-3 real gals.