The lady I saw yesterday was 100% her in pictures
There are some genuine ads, but they are very much the minority.
The pictures are there to reel you in. Generally, the more a picture looks like a supermodel, the less likely it is to be real. As the saying goes, if it looks too good to be true, ......
I would never use VS for a spur of the moment booking. As Yorkie says, you need to do your research. At the very minimum, do a Google search on the phone number. If the same number has been used to advertise different girls, that is a good indication that it is b&s for example. It also pays to ignore new profiles, as that way you avoid the large number of fake profiles that only last a day or so.
I also view with suspicion any ad that only appears on VS (and sites such as Kommons that copy ads from VS). Why would a girl only advertise on VS, and not elsewhere? The most likely reason is because other sites won't accept the ad.