No, I think you're better off going with law review, and putting your heart and soul into your comment so you get published. Also, do what you can to have a presence on the journal (work hard on any assignment give), and make nice with journal members, so that when the time comes, you can hopefully land an executive board position.
Those 2 things will be far more helpful than ANYTHING you can do on moot court. Add to the fact that adding unnecessary stress in the form of moot court responsibilities, and you're facing even LESS time to put into classes than you'll have with OCI and law review, and LESS time to put into your note/comment, and possibly less of a likelihood of getting published.
Granted this is just my opinion, so take it FWIW.