I was diving at Guardalavaca this past oct , the diving was great the dive masters are accomodating and very professional .They would rather dive than cut sugar cane so your safety is very important to them . I would suggest that you stay at a resort that has a dive center attached to it. Brisas Guardalavaca would be a good choice. Exhibit good bouyancy skills and they will take you to the best reef and wall sites(they take the rookies to the beat up shallow reefs..) . Lots of fish including shark , barracuda , grouper . I am going to the Cienfuegos area(opposite coast) diving this week for the 3rd time , not only is the diving and visibility excellent( reef and deep wall ) but the total tab in cdn funds for this basic all inclusive resort including airfare is less than $ 600. An 8 dive package costs less than $200 U.S. So it costs less to go diving for a week than to stay home , well thats how i justify it anyway,
I was diving at Santa Lucia which is just down the coast from guardalavaca last April , again good diving , reef and wreck mostly , saw reef or bull sharks on most dives. All in all I prefer diving in cuba more than the keys, mexico or the dom. republic , less diving pressure and wonderful people that treat you as guests more than tourists. Cuba will never compete with the more exotic dive destinations but it is a terrific bargain for those that want to get away for a weeks diving without having to take out a second mortgage on the farm.
Doc, Sub mariner , I would be curious to know where your friends dove in Cuba . It is a huge island with hundreds of miles of coast and off shore reefs, A little research may have increased their diving pleasure.