Product review (4 stars): Works well and not too many parts.
We bought this one because it requires no electricity and has no motor. All you need is a little elbow grease. It fits a good amount of clothes and requires a very small amount of soap for a sudsy wash.
The suction cups are the strongest I've ever encountered, which can be a positive or a negative depending on if you really want the Wonder Wash to stay in one place.