I know the place but it's always best to call them before you go visit. It has happened to me that a private changed address between the time I first contacted them and the time I tried to make an appointment a week or two later. Now in all honesty I have to tell you that the reviews I've heard of this place are mixed so I think it will depend on luck whether you'll have a good time or not.
Just call them before you visit to find out who's working, go check it out and if you don't like it go somewhere else.
A few more asians in Prague:
Dajma 723 185 940(1.000 czk/1h, 20y, only Czech) located in Prague 8 close to Palmovka metrostation
Mila 774 811 546 (1.500czk/1h if I remember correctly, 22y, speaks English) works on and off so you'll need a little luck, she's located close to Mustek metrostation
Tina 776 579 389 (29y, speaks English) located in Prague 10