This winter we took a trip to Santiago de Cuba. We love Cuba for its beautiful beaches and freindly people. We have journeyed to Varadero, Havana, Cayo Largo, Cayo Coco and Santiago. The diving in Cuba varies greatly from place to place. Santiago definitely tops the list due mainly to its location. It is on the very Southern tip on the Carribean Sea side.
Dive operators are government run of course. We brought all our own equipment but their rental stuff looked fine. The inital dives are $30 per person per tank but decrease as you dive more. Thus it is not cheap but hey there is no competition.
Beaches in Cuba tend to have the softest white sand. My favorite beach location anywhere is Cayo Largo, Cuba. Walking in the sand there feels like walking in powder(icing) sugar. It is super soft, super white and goes on for miles. No one really lives on this Cayo. They fly staff in and out of the resorts for 20 day "tours of duty". The only exception are a couple scientists who live in the turtle reserve. We helped them release the baby turtles at sunset for their best chance of survival.