Staying at Moofushi - supposed to be brilliant for diving. Will check out Manta Point, cheers.
Moofushi's too far south to make a trip to Manta Point worthwhile - probably two hours+ by boat - during which time you'd pass dozens of other sites where it's entirely likely you'd find Mantas in abundance.
Have an absolute blast mate - it genuinely is a staggeringly beautiful country, although there is some political/social unrest on Male (the capital island) at the moment so take advice before visiting. SO jealous - I would seriously consider giving up a bollock for one more dive trip out there.