| I bought one, they are good, but I had a few problems with mine. Firstly it didn't quite fit properly onto my hose, so I was totally soaked by the end, this probably didn't help matters. Also hose + sponge isn't the way I clean a car, and it still had some dirty spots at the end. The windows didn't look good at all, but the paintwork that had been done properly (90%) did come out looking really smooth.
I guess it's just a matter of fine tuning the process. I'm going to try the flash shampoo in my big car scrubbing brush 'thingy' and then rinse off with the flash 'thingy', think that'll improve my results. Reading the above though I might take it back if it doesn't fit right again... | 
