I was in Provo two years ago. We used Provo Turtle Divers and was pleased with the quality but not the quantity. We like to dive lots and found this difficult due to their (everyone's) laid back attitude and distance to the better diving. They offer a 3 dive day, 1 day a week and two dives the other days. Unfortunately it was the day before we were to fly. We only managed 10 dives in a week, partially due to our night dive getting rained out.
The better diving is at Northwest Point or West Caicos. Grace bay, their version of seven mile beach, is mediocre for diving. You should insist that they take you elsewhere after 1st day checkout dives. The walls are spectacular. You have to see the beach with the Tiki Huts at Northwest Point. It's the best beach I have ever seen. You will probably get to do your surface interval there while diving Northwest Point.
I was only at the Allegro at the casino (not my usual cup of tea). Most of the restauraunts on the island are very good but very expensive.
As you can see the resorts are sparsely located, unlike Grand Cayman. I will defenitely go back but probably on a live-aboard.