SM, I don't use Vivastreet either (having tried it briefly years ago and found the callers horrendous), but to compare them unfavourably with Adultwork and most especially their customer service when you haven't even tried them is just silly.
Adultwork is a dedicated adult site with experience in advertising prostitution, webcamming and so on - Vivastreet is a general classifieds site with a prossie section; it's more useful to compare it with newspaper ads than purpose built directories. They certainly do make cock ups, but so do AW and theirs are often worse - ask the people who have suddenly had their ads deleted without being told why or whose ID/face pictures have appeared publicly all of a sudden. Nor do VS demand ridiculous amounts of personal information from new advertisers.
They also have a dedicated email and phone line for people to call who are having problems, which is more than AW have ever had; their customer service for anything that can't be neatly covered by a couple of ticked boxes is a joke. Of course people are going to post here if things go wrong, but like everything else more people tend to complain about the bad than praise the good and it can make things look a bit skewed. There's really no need for the above when you haven't even tried it.