I just got back on Sunday from 5 days diving in Malapascua with Exotic. I highly recommend them. The guides have sharp eyes which is important when much of the great stuff to see there is smaller than your fingernail. We managed to find the threshers on the only morning we went out looking despite the comparatively late 7:00 a.m. dive time.
Depending on how keen you are to return to sites numerous times, I would think that 5 days there would be enough to see a lifetime's worth of awesome critters. Just a sampling of what we saw in 15 dives: We got to see plenty of sea snakes, pygmy seahorses, frogfish, wonderpus, pipefishes, the largest flying gurnard on the planet, as well as dozens of different species of nudibranchs, lionfish, shrimp (including the harlequin, hundreds of banded-cleaners and glass anemones) and crabs (including porcelain and spider).
Depending on how keen you are to return to sites numerous times, I would think that 5 days there would be enough to see a lifetime's worth of awesome critters. Just a sampling of what we saw in 15 dives: We got to see plenty of sea snakes, pygmy seahorses, frogfish, wonderpus, pipefishes, the largest flying gurnard on the planet, as well as dozens of different species of nudibranchs, lionfish, shrimp (including the harlequin, hundreds of banded-cleaners and glass anemones) and crabs (including porcelain and spider).