Anybody use a particular service?

I've tried to be pretty particular about who I give my number to, especially when I use things like Craigslist, so I went searching and searching. A few good ones are invite only (I read a report on Numbr from a blog I respect) so I did some more searching and am trying out a service called Jangl (free in beta).

Anybody tried services before, though? How have they worked for you?