Regarding Yantra, I was told by a girl from Society Service that Yantra is a legitimate agency, and they do have some very nice, very gorgeous girls, however, they don't have a lot of girls, so the lady who runs Yantra pads her site a bit with stock images. I assume if you contact them asking about one of the fake girls, they'll tell you she isn't available and suggest one of their real girls. Still not the most honest way to do business, but it does seem like you might not get completely fucked over if you book a girl with them.