That's pretty amazingly realistic - a heck of a lot better job than the rather ugly "Real Reef Rock" man-made stuff (that's just my opinion - some folks like the garish purple color).
But from the standpoint of actually providing some biofiltration, you'd be better off by either cycling some natural dry rock yourself (like Marco Rock's material), or better yet, ceramic bio-filtration media such as Eheim's substrat pro or Marine Pure's ceramic bio-blocks. What one needs for bio-filtration is surface area, and actual live rock or one of these substitutes has a massive amount of surface area relative to the volume of the media.
The potential advantage to one of the ceramic substitutes is that in the event you get a fish that has ich, marine velvet or another marine parasite, the media can be easily sterilized with a little bit of bleach or even by just soaking it in RODI water after you cure the fish.