We did this dive in 2005 with Jack's. There were at least 12 mantas there that night. Words of advice, overweight a lot, the turbulence will pick you right off the bottom. Our dive briefing said don't touch the mantas. THEIR dive briefing included no such instructions!
I agree with the added weight but who do you mean when you say "THIER"? Big Island Divers were pretty emphatic about the no-touch policy to us divers and to the PDV's (snorklers).
Dave