Cruz Bay Water Sports at the Westin, also a shop in town. Day dives (2 tank a.m., 1 tank p.m.) Excellent & experienced. Good rental gear if you don't have your own. St. John diving is about 7-8 on Caribbean scale, but CBWS is 8-9. Best dive is all day to the Rhone in BVI. (You'll need passport for that one. ) Worth doing, enough that we have done about 40 dives on her and are going back.
M & J H