well immediately I can see a dimpled surface on the reflector, that can't be good for reflection, with lumenarcs you can see multiply reflections of the bulb itself, that shows you that light is getting to you without interruption without the light being turned on!
I had the old PFO style (dimpled) reflector that I thought was good. I went and got the Lumenarc mini DE pendant. No comparison. Lumernarc blows it away. Much more light spread and the tank appears brighter.
Only the corners of the LumenMax reflectors are the diffuse type surface and the rest of the reflective area is specular like the LumenArcs. I would expect them to perform very well.
According to Sanjay's tests the full size LumenMax reflectors performed as well (actually slightly better) as the full size LumenArcs. Look at the summary charts in his articles...