Why I choose utterances as my blog's comment system?

Pros

• I prefer to put all my stuff on github
• My theme, minimo, has already supported utterances
• I can receive email about new issue from github.
• I love the simplicity provided by utterances.

Cons

• User must have a github account to comment.
• Can't prevent bad guy from putting spam comments on my blog, but I can track who did this.
• My blog site is slower