I have a Rotovac 360 I use in my
Portland carpet cleaning business. It works phenomenally!! Here is a video where you can see it in action:
Rotovac carpet cleaning
They are great because they are light, so you can use them on the stairs. They don't need a big motor, because they are like half the weigh of the RX20. They have a tile attachment that works great!
They separate and lift each fiber, helping to restore worn out crushed and matted carpets to like new condition. Wands can't do this. I tried all the Rotovac machines at the factory in Seattle and chose the 360.
You should have seen some of the carpets I restored using a portable and a 360!!!
http://www.seanscarpetcare.com