Product review (4 stars): To make this work...
I have owned the Wonder Washer for more than a year.  Thru trial and error, this is what I find works best:

1) Load clothes in a separate 3.5 gallon bucket. About 2/3 full, loose and not packed down.

2) Place in bathtub and use shower to fill bucket.  I add a small amount of detergent, diluted with water on top of the clothes as the hot shower is running (I have a watersaver hi-pressure shower head) This adds some extra cleaning time to the clothes

3) Transfer clothes and water (the proper fill level is trial and error- the minimum as long as the clothes turn and without splashing over)to the Wonderwasher bucket.  I have the WW sitting on top of 3 foam exercise square mats with a plastic serving tray that the WW sits in.  This helps with noise and contains splashes.  I also wipe the WW bucket, motor base and the tray so I can monitor if water is splashing out

4) Adjust time and cycle.  I've been using 9 minutes and gentle cycle (I think the gentle spins for 7 seconds- 3 second rest- 7 sec. spin- repeat. The Standard cycle is 14 sec spin- but was beating up and stretching socks and long sleeves)  I add fabric softener when I am starting the machine so the clothes are less wrinkled.

5) Then I take the WW lid off, walk the bucket to the tub and pour off the water and clothes into a plastic dish rack (that has raised legs) and lets the water drain off.

6) then I quickly hand wring out clothes and place them in the bathroom sink, fill with water, drain.  I do a quick hand wring again (not overdoing it) and place them in a spin dryer for 5 minutes (similar size to the WW) which spins at 1500 RPM.  Then I put the clothes on a folding rack and they are usually dry by the morning.

7)  This is an example of the spin dryer (not sure if link is allowed)
I spent $[...] on this item.  Hand wringing wasn't working well for me.

[...]
 If you do use this it is very sensitive to being loaded with the heaviest cotton items first on the bottom.  Again there is trial and error learning this.

8) I think the WW can do a great job cleaning clothes.  The above steps are a little labor intensive, but to me gives the best cleaning, rinse, wringing without using too much water.

The grey/black water some reviewers complained about is color coming out of the clothes because the WW does agitate and spin the clothes very well.  I'm amazed how many items aren't colorfast.

Hope this helps