Right now they are doing a special offer you can't refuse -- 200 credits (that's 20 minutes chat) at no cost, you just have to give over your credit card number for verification.
Obviously the idea is that you'll like it so much you'll stick around a buy something in future!
Still worth a try, particularly if you like the "cute girl" look which seems to be their focus.
Ok a brief update on the below -- the basic facts are the same but a lot of the girls have changed.
: Although they still do not take individual models there is now an invitation for studios to contact them though, and they are looking for male rooms too.
16 Nov 04: Secret Friends, previously run by a company called Pleasure Labs, is now apparently either changed their name or been bought out and are now "".
They also now seem to be associated with mycamfriends.