For those who are on the fence about SA due to some of the negative stuff written, I still say it is potentially worth it for some. The major hurdle is time & your budget. If you want model level who can hold a intelligent conversation, fun & GFE, it will probably be a bit costly. Of course, there is always the not so good looking older mother of 6 looking for a few quick bucks, sure there is a price for that.
Worth it is always arbitrary.
If your time & budget allows, its very possible to have a nice rolodex of SB. A lot of them are fine with per meet arrangement.