The claims of both are essentially the same. My opinion is your will see minimal effect on nitrate level using either product. I have no doubt they are both great biological filtration media products, but the claim that they will allow anaerobic bacteria to colonize is pretty bold, given the flow rates through most folk's filter systems. I would think in order for there to be any anaerobic colonization you would need to set this media up in it's own very low flow reactor, as opposed to using in a normal filter. Even then, the results would probably not be mind blowing.
What it comes down to is basically yes, these products provide some great surface area for biological filtration, but the best way to remove nitrates in a FW
system is through exporting nutrients the old fashioned way - water changes