The 3 dive operators listed by Dive Maven are all good, but their focus differs a bit.
B&B is the one most likely to have lots of other divers with <50 dive experience. They are my preferred boat when going out with either new divers, or divers that have been out of the water a while.
Mike Severns is very much critter / marine life / biology oriented. They also do quite a few dive sites that others don't go to. The find these via their side scan sonar, and through dives done by the Capt and mate while the customers have their SI.
Ed Robinson has two boats most days and offers some more aggressive diving than the other two.
All three operators are 12 passenger boats that normally dive as two DM-led groups of 6, that are roughly grouped by experience level.
Specific dive sites are chosen after discussions with divers onboard and based upon sea and wind conditions. The most common trip is a first dive out at Molokini and a 2nd dive back closer to shore.
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If you will be diving for multiple days, you should consider driving 50 minutes to Lahaina on one of the days, and taking a trip to Lanai. Extended Horizons is my preferred 12 passenger boat, and leaves from the Mala ramp. Bigger boats by Lahaina Divers (better for divers prone to sea sickness) leave from Lahaina harbor.
