Staff was consistently friendly and concerned about my experience. Each and every one expressed a sincere interest in making sure that I had what I needed and felt comfortable.
The grounds are very well kept though travelers should definitely bring something to ward off sand fleas who are relentless. The rooms were very simple - plywood walls, minimal lighting - but very clean and sufficiently spacious to accommodate a single and double bed with a comfortable chair, nightstand and dresser. There seemed to be plenty of room for scuba gear. The bathroom was generously sized with a stall shower, bench, toilet, and sink. (I had plently of hot water though others in our group did not.) There was also a large closet (the only one) in this room. My only complaints were with a noisy air conditioner and the lack of adequate lighting to read at night. Double bed was firm with three pillows and a spread.
The dining room is pleasantly laid out and comfortable with open doors and overhead fans. Meals were served very promptly and pleasantly. Breakfast was consistently good - cooked to order eggs and meats with daily specials like pancakes or waffles. Fresh fruit was served at most meals. Lunches and dinners were best when simple broiled fish with fresh local vegetables.
The scuba dive operation was staffed by a competent and helpful crew. I also had an excellent snorkel run with an eagle-eyed diver who pointed out many creatures that I might have missed (like a porcupine fish hiding under a coral shelf). I am partly disabled by MS and could count on a hand whenever I needed it.
And, last but not least, the director of Blue Marlin ordered a birthday cake for me as a surprise. I was surprised but probably shouldn't have been since it seemed completely in character for this charming group.