Every once in a while, an article comes out that tells me exactly what I need to know about a system. This is one of those articles.
Polished Concrete Outshines Other Flooring Options - EBN: 15:2
It's what I would have told you myself, plus quite a bit I didn't know or hadn't thought about. Like the acoustical effects of polished concrete, and the relative costs. I suspect that I'll be coming back over and over again to refer to this one.