I know these have been talked about a bit here before, so I thought I'd just provide my own personal experience...
Harborfreight had the 2.5 quart model on sale recently for $74.99, and with an additional 20% off coupon code for online orders, I decided I'd take a gamble and give it a shot. I was able to get it out of the box last night and was going to give it a shot, and then I realized I was out of simple green. Crap....The only thing I could find in the house to use was some of that orange TKO cleaner / degreaser stuff my wife bought awhile ago....so I tossed a teaspoon of that, filled it up with water and threw in and old carb I had kicking around to see what happened.
First observation was that it was way louder than I thought it would be.....So I plunked it into my basement and went down every 10 minutes to reset the cycle (480 seconds is the longest cleaning cycle you can set it for), ran it three times (total of 24 minutes), pulled the carb out and to my surprise, it was very clean. I used a q-tip to remove some of the loose grime on the outside, but aside from that, it turned out really well. I was actually pleasantly surprised....
I'm going to go pick up some simple green tonight and toss in the jets, and try it out again...I'll try to post some before and after pictures.