I just stayed at the Marriot in Costa Rica on the all inclusive. It was incredible. We must have averaged $150-200 per day which covered all the alcohol you could drink and eat at any restaurant on the property. The food was outstanding. One caveat, if you wanted to eat the lobster it was a $15 upcharge. I chose to stick with the covered menu during my stay. By the way, I am margarita'd out. I leave tommorrow from Costa Rica to the US but would highly recommend the "all inclusive". It was nice not to worry about what drinks cost or how much a meal was going to be. Good luck!!!
We stayed at the Marriott Frenchman's reef (St. Thomas) over labor day and we ate and drank at the hotel a couple of days and boy-oh-boy did it get expensive. I *mistakenly* had 5 frozen vodka lemonade's at the pool one day at $11/12 each -- thinking they were probably $5 - 8 each. My husband was also drinking that day...then we decided we ought to eat on property rather than drive ourselves anywhere... Dinner was easily $150 without trying too hard. All in that one day cost us cash near $300. This didn't include the buffet breakfast at $24 pp nor lunch.... If I would have known about the option to buy all inclusive, I would have done it - at least for a couple of days... Not that there are a ton of fantastic restauarants in St. Thomas (albeit we are a bit spoiled, living and eating in Chicago...) but it is certainly fun to get out and meet the locals and try the variety of restuarants off property. If Havana Blue is included in the STT option -- you should DEFINITELY buy the AI.
There are a number of posts regarding the Inclusive Reward. There's a good mix listing pros and cons. To find them, consider using Search or Advanced Search and browsing the results.
The Marriott Rewards Forum is very popular and posts scroll off the main Forum board because the space is limited to the most recent 3. You did the right thing by reaching out seeking additonal input, By browsing 'backwards' I saw your post.