Between the following resorts - which do you think is the best option?

SPG - (not the Westin) - midprice

Westin - midprice, though higher than Sheraton

InterContinental Presidente - cheapest

Marriott Casa Magna - most expensive

I don't believe there are any Hilton properties down there?

I'm heading down for a 3-day weekend in March with a girl (who is just a friend - so the room will have 2 beds, not 1 ) and we're looking for a good place to relax and read on the beach (or by a pool) during the day, and get wasted drunk at night. It would be nice to be near other things as we are not renting a car & will have to rely on taxi service or public transportation for everything.

From the pictures, the Westin & Marriott look the best - but I know next to nothing about their location (is this anything like CUN where there's a specific hotel zone?). I'm more interested in doing a brand name (quality guaranteed, generally & of course, the points!) resort if possible...

Thanks in advance!