I am pretty sure I saw a post recently where one person said that he ranks well purely on scrapebox and xrumer blasts...some people spam the hell out of comments with scrapebox and all the comments go to the money site. When I see the same site again and again, I do a SERP check and more often than not, they seem to rank well.
By the way, I had a site for a foreign country site with low competition that is currently ranking on number 5 for its main keyword. All I ever did to it was send about 2,500 backlinks with scrapebox. It was sandboxed for a couple of months but then settled on the first page. I have not done anything else to it.