Heck, you might even love him all the more for the quirks you would find annoying in anybody else.2.
You're more or less aware of each other's relationship history.
Sure, the transition from friend-to-boyfriend might feel a little weird at first, but we think that the benefits of dating one might just overrule the awkwardness.1. Let's face it, during the first few months of dating someone new, it's easy to hold yourself together and pretend like you don't have a dark side (everybody has one).
You downplay your insecurities in hope that he won't see you as clingy, and you supress the fact that you occasionally get moody, jealous, or pointlessly angry.
As a friend, he will not only be aware of your personal weaknesses, but he will know how to respond to them in a way that is constructive to the relationship and to your desire to improve yourself.