In your opinion what is the BEST Marriott/Renaissance/Ritz Carlton in the Caribbean, including Cancun? Criteria are:

Great beach
Great facilities, newest furnishings, spa, restaurants, etc.
Kid-friendly

Also, does anyone have any opinions on the Los Suenos Marriott on the beach in Costa Rica?

I would say the best RC is in St Thomas, but I've stayed at both, and the one in Cancun is also VERY nice.

St. Kitts Marriott is brand new and gorgeous.

Except the beaches at the St. Kitts Marriott and Ritz St. Thomas aren't anything special. And the Marriott, while new, is still just a Marriott. It's not as luxurious as a typical Ritz Carlton--you can tell just from watching the video below. Here's a photo montage and a long video clip of the new Marriott:
http://www.royalbeachcasino.net/flash.html
http://community.webshots.com/album/70095301AOvDQb

Unfortunately, I think that the Ritz has greatly cut back on the number of rooms available with Marriott points ( I assume that this is why you asked for the info).
I tried for any and all weeks(using Marriott points) at the Ritz in STT and Cancun and they have no openings between the end of December until the end of April, 2004.....and I did this search about a month ago.
We ended up with the JW in Cancun in January...still a nice property.
I think that the Renaissance is STT is the most kid - friendly....
I, too , would be interested in learning more about Costa Rica. Good luck!

To clarify my post, my sister is looking for the best resort; if she can't use Marriott points at that resort, that is OK. Her preference is the best resort, not the best available resort using Marriott points.

Thanks to everyone so far for their opinions.

ttt