I booked Grand Luxxe 2 bedroom 2 bath suite on DEX (I have HVC, formally DRI) for a single deeded week (Las Vegas) plus resort fee of $150. There are other small fees that don't come to that much more (taxes). There was a $179 exchange fee and $89 insurance (optional for the deposit if we cancelled). (Actually, I used two weeks to book two suites 2 bedroom 2 bath suites but I was quoting the one suite price).
We were not in Riviera Maya, but we picked the longer trip to Nuevo Vallarta because I thought my family would like that resort more. They loved it and were very impressed.
Our trip was July 4-11, this year. It was hot, but just a bit more than it was in the US NE.
The deal with DEX or HGV is real, I would highly recommend it over using RCI. We used II in the past to get Grand Luxxe, but those days are over with the now high resort fees.
Bonus. When we got there we refused the presentation, but we were put in GL 4 not GL 2 that we requested. Leaving, we were offered GL 3 third floor, facing the river and PV (above the first floor, planta baja, with vegetation view and mosquitos. And they made them villas instead of suites, plus breakfast for all 7 of us. My wife who won't do presentations relented. After breakfast, our guide said since we know the resort so well, instead of a model tour, let's all go on the gondola instead! End report, the talk was mild, no hard sell and we were out in an hour.