Last januari I was on Phu Quoc Island and did 2 days of diving with Rainbow divers. Compliments to the girl who checked us in. She asked for my certification card before she started about the different dive sites.
She took the time to tell about the diving around the Island and where the "best" places where to go to. Phu Quoc is not famous for its reefs and she never told us it was :)
Lunch on the boat was great, fresh and tasteful. The DM did a good briefing before we jumped in. He was a bit in a hurry though.
All in all I would definitely recommend diving with Rainbow divers. I dived lots of places and seen a lot of crew but these guys are worth every penny!