I certainly get enquiries from AdultZone. Also, the owner, Sharon, is very nice to deal with, and they've made a few developments recently in terms of the info you can provide, reviews etc. I've not been focusing on my advertising for a while as my civvy job has been all-consuming, but when I have the time I will be taking a look at AdultZone and refreshing my content.
If nothing else, just making the most of the free options isn't going to hurt.