I recently worked on a project where I had to weigh the same things. In the end, I decided to leave my comments.
Namely, the advantage of your own game is that you have complete control over how they work. I needed a moderation / queue system in which I needed to work in a certain way, for one. Secondly, someday I will try to integrate the community reputation system, so this was another plus for my own. I don’t want to leave such things to a third-party decision outside my control, and third parties do not always have such a flexible API for change.
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, - Railscasts Gem http://railscasts.com/episodes/262-trees-with-ancestry, .