Back from Grand Cayman, and going to let people know it does depend on prevailing winds.
Wind was from SE, meaning North Shore was protected. Went out with Deep Blue Divers (
www.deepbluediverscayman.com), and was very pleased with their operation. They run 2 Dusky dive boats, 8 people max/each, and I got to dive 4 sites on the North side, then 2 on the South Side. They were very professional, yet fun. Nick and Patrick do a great job at the sites. Saw lots of wildlife (hammerhead, turtles, tons of other fish, stingray, etc).
Thanks for everyone's input. There is also cool shore diving, got to do two sites, one with SunDown Divers (?), below Cracked Conch restaurant, on NW side (very well run store), and Eden Rock Dive Center (consistently rude on two visits).
Island is a bit pricier than other sites in Carribean, but pretty good. Sites more impacted than I thought they'd be, with lots of overfishing evident (many, many large lobsters on reefs, which you would not expect with normal "large" groupers in residence). The drop-offs to nothing are spectacular (4000+ feet verticals).