We've stayed there several times (when it was Oasis Akumal & Gransd), very nice place. Try to get a condo room in building A-D. Huge rooms and right on the beach and the best area of the beach. The rooms on the other side of the resort on the beach (by piers) are part of the Vero Club, and you will be blown out by loud music and Italians. There is really no beach on that side mostly rocks.
You can walk down to the Bahia and get gifts in thier huge market area, they have and ATM, sports bar and a bunch of vendors.
We dove with the shop there with no problems, they will take you to the main dive area in Akumal to catch the boats. It's about 5 minutes away, and the resort there has an ATM if you need some cash. Their prices are in line with the rest of the shops in Akumal. Bring your own grear if possible, ant take it back to your room each night to dry, their srtorage is a "not so safe" looking shed, better safe than sorry...
What ever you do stay away from Villa De Rosa or Cenote Divers down the road, they will screw you on open water dives and try to get you to cenote dive with them instead..
