I'm looking at the Sheraton Vistana Resort now, too, but can't tell if it has the "essential" waterside. The pool pictures I can find aren't very helpful. The price is good, though, and it looks nice.
I am hesitant to rent a timeshare. Is that crazy? I just feel like the quality and cleanliness varies so much. I am also sort of a germaphobe, and only want a place that has bedding washed between guests. My family likes the weight of blankets to sleep but if I go someplace and find the old type of spreads they go right in the closet.