Review (2/5): You get what you pay for
With this, I spent a good amount of time cleaning some brushes that were absolutely, completely, terribly filthy. Just scrubbing them on a cleaning mat would have taken quite a bit longer and wouldn't have gotten them all nice and fluffy again. After all my brushes were like new, I started cleaning my foundation brushes after every use and it took a just minute every morning. I really loved this thing. But it stopped working so quickly. :( I know this was cheap, but it hardly lasted any time at all.
Anyway, I saw the complaint that it slowed down when it touched the soapy water, but I found it still cleaned just fine despite that. I typically just dipped and held the brush at an angle, occasionally pulling it up a little before dipping it back down.