Aqua Scuba had us getting up at 5am and waiting at the pier at 6am for two days in a row, only to find out our diving trip to the great blue hole is canceled last minute. Twice. We got a full refund and booked with a decent diving agency for the third day. If you have the time and don't mind saving at least three days for only one day of diving, the low price (250usd) is worth the gamble. Else, go with a reliable company.