I really don't know why people say "adultwork is going downhill". To me, adultwork plus this site are the best way to punt. AW has the best search functionality, it's easy to navigate, and all the girls worth visiting are using it. Vivastreet comes close, but it's far more open to b&s in my own experience, since girls create adverts on their instead of profiles like on AW. AW requires consistency, those other sites don't.
Use AW +UKP and you'll have a good time most of the time.