Product review (4 stars): A Very Good Handwashing Alternative
I have no idea how I happened to have obtained a counterfeit version of this product sometime in the past, but suffice it to say that it was worth it to replace that.  This is the brand name product, and it is definitely superior in many ways.  It does an excellent job of washing, and is great for handwashables.  However, it is not foolproof.  As mentioned by a previous reviewer, pet fur (and lint) will remain on the laundered items.  Also, items washed in the Wonder Wash will come out of it very wet, and can take a long time to dry unless you wring them out extremely well (and not all laundry wrings out effectively), or use a centrifugal dryer (a large salad spinner can help in a pinch, although it is nowhere near as fast or as effective).

There are a few things which could stand improving.  For some reason, the lid doesn't always go on tightly enough or lock, and can come loose or fall off as the barrel is being turned, which results in a mess; so check it carefully, and make the first turn slowly.  The suction cups on the base can be a hazard if you need to move this to drain it:  lifting it with your hands under the barrel, rather than holding the stand, works well.  Also, it can sometimes be easier to drain the barrel from the lid opening.

There is a version of the instructions which gives temperature guidelines.  If you're in the United States, keep in mind that these temperatures (at least on the version I have) are in celsius.  A laser thermometer, if you have one, makes it easy to measure the water temperature.