I've tried their packages, but not with impressive results, for some terms with no great competition.
Also, I have a hard time finding the pages/profiles where my link should be on, in google.
I have also seen some posts about google not liking 'profile spam' and such.
What are your experiences. Does it work for you or not? Have you tried to rely solely on their packages (I know you should diversify, but am interested in this)?
How fast do you see results?