I first thought I didn't like it. I'd say my jury is still out, but it has 3.5 out of 5 stars or so. (keeping in mind I don't blowdry my hair)
It's something of a PITA (hard to clean hair out of, the micro-fiber-y-bits mat down easily and have to be 'fluffed')--it had instructions that one actually has to READ, for a frickin hairbrush.
It's supposed to be anti-microbial, so the spongeys don't get fungal gross
That being said, it seems to actually work. My hair doesn't feel significantly drier when I use it, but an hour later, it's significantly drier than it would be if I hadn't used it.
Basically, it dries my hair as much as a really, really REALLY agressive towel-drying would do.
But a really agressive towel drying leaves my hair all snarly...this leaves my hair all brushed out.
(It doesn't have the 'real' bristles quite as thick or quite as widely spaced as I would do. And if I made it, I'd make the spongy bits be somehow removable and washable)