The older Marriott DSVI 1-bed is largest, and SV Enclaves smallest (at least, that's the way it seemed to me). SV Enclaves pool was salt water when I was there a few years ago, which was nice compared to the others.
In the area I've been to DSVII (and seen DSVI), SV, SVE, along with Club Intrawest, Westin Desert Willow, Westin Mission Hills. Desert Willow is my favorite, though it doesn't have an associated hotel (which, after my last few experiences, really isn't anything to write home about), and Desert Willow is the newest of all. Typically, any of these resorts are readily available for trade during off season.
I actually enjoy the heat in August, though it is quite hot. But I also enjoy the aircon those days, too...
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