I remember HD800 with GSX was quite similar to the 009 and BHSE combo. Not the same, but close. When I heard them thou, HD800 was terminated SE. Also, I have the HD600 and I could see how even combining them with the GSX would not bring them up to the level to compete with the ultimate electrostatic set up that is the 009+BHSE.
Prepro, I think we will have to the chance to hear both at the DC meet. It will def be nice to compare even in meet conditions. I have since gotten balanced cable for the HD800 so it will be interesting to compare when both (the 800 and the 009) are in optimal configuration.
As a side note David, I think the HD800 and the HD600 are miles apart, performance wise. There really is no contest there. I understand being financially strapped (furlough here I come) and with 009 + BHSE I would not itch for the hd800. If you ever get a chance, check it out. They are nice cans, and if you like big sound stage, they beat the 009 in that department.