Just returned yesterday from my dive trip to the Maldives. This was my second trip to the islands: the first was resort-based while this one was on a liveaboard. The experiences were significantly different.
In discussing this impression with the captain and dive cordinator of the boat I was on, I learned why. Resorts tend to attract a mixed selection of divers ranging from open water students to experienced divers. LOBs on the other hand appeal more to divers with a higher average number of dives "under their (weight) belts." Because of the differing clientele, safari boats (LOBs) consciously select somewhat more challenging dive sites while resorts avoid them.
I should point out that my liveaboard experience was probably not typical of what normally takes place on a Maldives LOB. I was with a group that had chartered the Giulia (more below in reference to the boat) for a 12 day photo safari. Because the trip was organized by a respected underwater photographer and the group included both amateurs and pros, divers were required to be experienced and to have excellent bouyancy skills in order to handle some of the more challenging dives and still take pictures. The diver with the least experience had 100 dives (and a great camera). In most cases we all jumped in together but ended up split up into our buddy teams as the picture taking and filming took us to different spots on the reef. With a group like that, it's especially important that divers be highly competent.
We dived channels and fast drifts quite a lot, but we also did some "easy" dives. When we were looking for big animals, we often had to swim against a moderate current (1 to 2 knots), whereas when the aim of the dive was to explore a pretty reef, we did slow drifts where we could stop and check out little stuff. The wildest ride was at Maalhoss Thila where the 2 to 3 knot current with a washing machine effect swept us along a reef wall where the only refuge was in the large caverns overhung with soft corals (for good reason the site is also called Blue Caves). I've attached one photo of a big animal and one of a little one.
The Giulia is a brand-new boat in its innaugural season, having just begun sailing in mid-February. It's very comfortable, has large cabins with private bathrooms, and offers plenty of both open and covered deck space both on the main deck and on the sun deck. There's a large lounge area with dining tables, an alcove with sofas and a flat-screen video display for viewing footage shot during the day, and a computer room with space to recharge batteries. The food was good, too, and the cook made a special effort to include delicious veggie main dishes for me and one other guest. Diving takes place from a dive dhoni where equipment is stored and tanks are filled. The dhoni has seen a fair amount of wear, and it shows, but it does the trick. The crew are helpful to a fault, going so far as to wash all the gear for the guests at the end of the trip. The Giulia is the newest addition to the Seafari Adventures fleet, and while there are still a few minor details to take care of (for example, the reading lights above the beds weren't connected yet), it can only get even better as the season goes on.