For me it depends on what services they offer too and how friendly they are likely to be on meeting me, can't be meeting one with a stuck up bitchy attitude that most models have. I wouldn't meet one on looks alone.
For a genuine pageant girl / pro model offering every service I am seeking for, with the right attitude, maybe up to £500 per hour? She would have to be nothing less than perfect though.
In all honesty, like how another member has said, the contestants in your link don't appeal to me on first look though. I wouldn't pay anywhere near £500 for them and that's without knowing what services they offer in exchange.