I had a rotovac and a 360 from Alltec for a few days on trial,
Never tried the 360 as it was faulty, trigger never turned off. (Brand new)!!!
rotovac i found to be not that good, fiddly to get perfectly set, used masses of water
or didn't clean that well, and left the carpets very damp.
tested with Ninja and Powrflite.
If it cost a lot less then maybe i would consider it, but i found it slower than a wonderwand.