I booked a one hour massage here and my service was great! The spa is very tranquil and a great place to relax and unwind. Since the Vdara is a smaller hotel, you can enjoy the fact that the spa will not be overcrowded and you will be using the common facilities alone often times (sauna, pools, locker area, etc). I went to the Aria during my vacation for another spa treatment and did not have a great experience because it was overcrowded and had several coed facilities.
If you are looking for a quiet and small facility to relax this is the place. My experience was enjoyable from beginning to end.