We spent 2 weeks (Dec 18, 2010 to Jan 1, 2011) there with our 16 year old twins, it was supposed to be just my wife an I, but the twins whined enough that we took them too, so much for a romantic vacation...
When reading in these reviews I see comments about the lack of maid service and one complained about insufficient towels/linens. I find these comments odd because they are complaining about "Costa Bonita" when it was not "Costa Bonita" renting them the condo, they rented a privately owned condo that happens to be in the "Costa Bonita" complex. They should take it up with the people they rented the condo from, not complain about the complex where the condo is situated in... As for organized activities, there are none, the building is not a hotel; the condos are all private residences in a complex on the beach. You have to find/make your own activities. This is probably not the place to stay if plan on spending all your time at the complex expecting to be entertained.
The condo and the resort is extremely clean and well kept. The restaurant and bar is run as a not-for-profit by the HOA so the prices are very low. There is a huge selection of books to trade in the room behind the jacuzzi. We found the snowbirds to be friendly and outgoing. It is a quiet place, no organized activities, but one of the snowbird ladies gives free water exercise classes each morning. We spent most of the time exploring Mazatlan, We signed up for several trips, rented a Hobie Cat 4 times (1 hour each time). we booked the Huana Coa Canopy Adventure zip line tour (12 lines) at the tour desk, what a blast!!!!!! They even include beers or soft drinks and a great Mexican cheese fondue meal after the zipppppingggggg. The guys are really funny and they know what they are doing, highly recommended!
The resort beach area is gently sloped, it does not drop off quickly like it does in many other parts of Mazatlan, you can walk out a long ways before it gets deep. The Golden Zone is around 10 minutes away by bus (60 cents), there is a bus every few minutes, so we didn't bother with a taxi (around 7 dollars) unless we were going back to the condo with a lot of purchases.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC