That would certainly do a larger load than the Wonder Wash, but then it also takes up more space. It also appears to be missing the same thing the Wonder Wash does, which is a way to wring the water out of the clothes after rinsing. If that has a way to spin-dry (or mostly dry to the point they can be hung up without hand-wringing) then it seems a winner, at least for the summer.
Creator of Shire Silver, a precious metals based currency. I work on a permaculture farm. Old nerd. Father.
The secret is to have a sealable drum and use hot water. When you turn the drum pressure builds up and forces the water through the cloth. I used to have a great little hand cranked washing machine that worked really well, and was just a sealed drum on a stand with a handle. I found if I chucked it in the back of the station wagon and drove to town and back it worked just as well.