[gregpark]

I've used Ardex products for many years but for floor stoning (prep). You could use it for a finished floor (and many have) but not over OSB. The Strands of the Oriented Strand Board swell at different rates when exposed to dampness and it'll look flat at first then funky. Ardex also does not cure hard enough to use as a floor covering, even with additive.
I've not done it but have seen OSB subfloor that has been sanded and finished with urethane like you would a hardwood surface. It works but not a great look IMO