I have not been to that one, but my hubby and I had massages at the Mandara over at Portofino Bay in October and they were exquisite...probably the best we've ever had (except for a cabana massage on Castaway Cay!).
Mandara can be pricey, but they are a high class spa with choice locations around the world.
We haven't had a chance yet to try the WDW spas, but I've heard good things about the spa at Sarasota Springs.