I have been on the site and chatted with three women, a 4th to use up my last credit in process. Perfect English and all very sexy. As soon as you insist on using your email address they go cold. I have a distinct feeling all the good looking, and some less so, women are employed, and their only purpose is to get mugs like us to buy credits and chat. I very much doubt you will ever get to f*** them.
Besides the message time differences noted above, have a look at their pen name and another name in their bio. Often different, and you know how people tend to look like their name (or is that just me?), well the bio name usually fits better, and tends to be foreign..
Try the site out. Buy the minimum credits for £8. When you send/receive a message the first time insist on using your email. If they don't come back via it you will only be 1 credit lost.
You can register several times with different names, your email address makes no difference. Get 2 free credits each time. The same group of girls match with you from the same region each time.
I think I will get a job with My Secret Sex Contact as a chatter-upper, and watch a bit of sex at the same time, could be interesting, and do it while my woman is there.