Addmefast can increase your site/page media activity and allows you to gain Facebook Likes, Google+ Circles, YouTube Subscribers, YouTube Visits, Web site hits and lots more (+).
But let's say that you'll use your own (personal) accounts: (-) the result will be bad as the quality of favorites thing go go crazy. On the other hand, if you'll use secondary accounts (and most of other Addmefast users will do that), will increases the risk of loosing points if those "voting accounts" are disabled/ deleted (-).
Generally, the positive appreciations have more relevancy if they are received from verified sources