Product review (4 stars): labor intensive but works as intended
Even when I had a washer/dryer in my apartment, I tended to do small loads and air dried all of my clothes.  So when I moved into a studio apartment without a washer/dryer, I figured this would work for me.  Growing up in the US, I only became aware of devices than the standard American washer/dryer when traveling to developing countries.

About the machine:  I read the reviews about people who received a pink Wonder Wash and at first I thought "oh good, I didn't receive a pink one" but after using it I realized it IS indeed pink.  It's odd because it's a very faded, almost unintentional pink, like there was just leftover pink residue in the machine when they made it.  Mine also doesn't have the Wonder Wash logo on it.  Additionally, it seemed used when I received it.  I just washed it out and I guess it's not a big deal, but I wanted to mention it.

I think it works fine.  There isn't much to say about the pros other than that it's not electric so it's unlikely to break and it works as intended.  I do have a few cons, however.  First is that unlike a washing machine, this does not extract the water very well in between the wash and rinse cycles.  So a lot of dirty water remains in the clothes.  You could rinse the clothes under running water but this gets very heavy.  I have been using my spin dryer in between the wash and rinse cycle.  Another con is that it's more labor intensive and messy than a washer.  Water seems to get everywhere, whether I do it in the tub or by the kitchen sink; have a rag nearby to clean up.  I'm not sure I buy some of the claims this makes --- it says you use less detergent.  But of course you'd use less detergent, it's a mini tub.  And I've read claims that the vacuum sealed chamber forces water through the clothes for improved efficiency.  Again, this could be true but I'm not sure I'm convinced.

All in all, I'm using this for now but might look for other solutions.  I'd love to see this with some way to extract the water.  Even just a device that squeezes some of the water out.  (By the way I bought a spin dryer that The Laundry Alternative sells and LOVE it).