I've done it a fair few times with some of the girls from the popular shops and never had an issue. BUT!! With that being said I have never done it with a girl who has offered it for a price or even have i done it in the shop with her. It's always the girls who are absolutely strict on using a condom and don't even entertain the idea of bare back sex whilst working that I have done it with. Call it risky but those girls I am more trusting with because if they are strictly condom all the time then I know that they don't do with other customers so the risk is low, but this only happens after I've seen her a few times and have built a rapport with her.