My test unit of the 7506 is Joma's which has probably seen better days hehe, but it is slightly more comfortable than the lux, the lux being a tad stiffer.
I am testing them both with the HA-3D amp with 3 output jacks so everything is sonically the exactly same which is a blessed relief when trying to a/b things.
Looking at both pads, the lux is nowhere near as worn as Joma's 7506 so the lux need a bit more break in there but even so the way they have made it with the slightly angled cups they would have been better with a leather headband than plastic wing system.
This is nit picking by the way, it pretty comfortable though the clamp is vice like.
As for the charts, I see but I dont really believe it haha... the lux is a lot more energetic in the top end.