Seems as if the track has stainless rollers on aluminum. How long is that going to last unless the aluminum has been hard anodized? More cost. Hmm, given how high the forces are, I'd expect it not to last awfully long even if it has been anodized. Some kind of plastic rollers seem safer. Maybe you guys can comment on what has held up better in your experience?

It's a beautiful part, but doubtful to be a cost competitive design. Of course, we gearheads will lust after parts like that just the same...