You know, I actually don't know! I'm inclined to think that it's a bit warm, since it seemed to take the edge off of the HD 800 at the top... and added a slight heft at the bottom. But in doing so, it made the HD 800 neutral, so maybe neutral? LOL!
I can definitely say that it was a good pairing with the HD 800, so I would think that it does well with brighter cans of all kinds.
Ha! I should have thought of asking this!
Touche!
Also, I built a little lightbox years ago out of foamcore and some muslin. Helps a lot in terms of not having crazy reflections of stuff in the room. Might be fun to try maybe?