I second that thread as great advice.
We had a horrible time at the Tides last year so wouldn't recommend it despite glowing Trip advisor reviews...

I tend to find trip advisor has a lot of one post reviews anyway from people that would find a marriot fantastic.
If you must go with trip advisor,then always pay more attention to people with lots of reviews under their belt and look at their contributions to see where else they've reviewed.
If they are giving 4 and 5 star ratings to otherwise 2 and 3 or 4 star ordinary hotels,then their opinion is to be discounted in my view.

Stick to the advice on this forum as to true luxury hotels from people who insist on standards and you won't go too far wrong.

Of the Riviera maya resorts,we spent a lot of time at the Mandarin.(we visited all the ones on Davido's list)It's beautifull and the service was very professional.We also had a very good michelin style meal at their main restaurant one night.