Well I saw a domain name at http://www.freshdrop.net/ and the domain was a reg free domain with "Number of Google search results with extension was over 110M"
Then the columns were sorted on backlinks and it showed the calculative amount.
As for PR I would have to join as a Pro member and I am not ready to do that.
So in general I was wondering what would be better Google, Overture, or Alexa backlinks.