I don't mind when the same ladies reply. It lets people know they're still available, and it's a form of free advertising that's allowed here.
On at least one occasion another persons' ISO thread for big girls (my thing) has steered me to someone I set up an appointment with. Of course, if I post an ISO, I like to receive PMs too.
I think you guys complaining that "it's always the same ladies who post" are just grumpy. If you don't want to read their posts, don't read em.
I like 'em, the kinkier the better... lol