Bought the W California King set (mattress and box springs) for less than $900 delivered - a genuine bargain. Then we bought the 3" feather bed topper at Macy's, along with some new sheets and a feather mattress cover - the sheets and other stuff cost more than the bed (but boy, they're really nice - better than the bedding at either W or Westin)!
And the best news? No more aching back in the morning. It's GREAT to be able to buy a bed that you know you'll be happy sleeping in; more mattress companies should work out a way to promote their beds via specific hotel chain 'test drives'.