FreeAxez raised flooring?

A consultant has recommended FreeAxez for the raised floor in a new data center. I checked it out and have concerns since it says it does NOT create a plenum and cannot be used as an air handling space; it's a low-profile flooring system. How would cooling be done in this scenario? Open air (with intake/exhaust mixing) seems like a step backwards in terms of efficiency. Descriptions of any operation experience with this product will be gratefully accepted. ~JasonG