Never ever use SB for tire 1 backlinks. U can use it for tier 2 backlinks. Also for tire 1 don't even use manual commenting from non related sites.
Actually ScrapeBox is excellent for what you mentioned http://www.scrapebox.com/manual-blog-commenter
Just because it can blast 100k lists, doesn't mean that's what you must do.![]()
"trust me, I have a mustache!"blast 500k comments using only 1 keyword and you will be fine.