Alden,

I can't speak for overseas properties, but I've been to all the luxury destination spas in the US. A quick look at the Canyon Ranch Tucson rates show about $1000 a night for an executive double, all-inclusive (and this is high season). You can't beat Tucson or Lenox for activities - there is no way to do even half of what is scheduled each day. I wouldn't recommend Lake Austin - too pricy for what you get.

Another option might be Canyon Ranch in Miami - I tried that last year and it was a good experience, although different than the two resorts. It's sort of a hybrid luxury hotel - destination spa, but not an immersive experience like the others. By far the best for luxury - even the standard rooms are huge and stunning, but obviously you are limited to that spot in North Miami Beach. You can add a meal plan for a reasonable amount. Of the two resort properties, the rooms in Lenox and Tucson are fine (especially because you are so busy you don't spend much time in the room). I think Lenox has some new larger renovated rooms that might be a step up. For me, bathrooms are a deal breaker and neither property excels in that area. The Miami property, however, is of the OMG class.

Good luck and have fun!