When you say "outperforming in every way", do you mean specifically the power output, and AM modulation percentage? Because that is the only two things that the 6666 has over the ARES2/QT40, in terms of "performance" that I have measured in all my testing. I know, those two things matter a lot to some, so I'm not arguing that, just pointing out what I have measured. FYI, I would choose the RX on the ARES2/QT40 over the 6666 every time. I find the 6666 hard to listen to after coming back to it from an ARES2 or 5555Nii. What are your thoughts on the RX?
Regarding the AT-500M, I agree, it's a little beast. I really like mine as well. Wait until the AT-500M2 is here, it takes all the original version goodness and adds a heap more features. The new M2 is a great little rig. It should be available any day now.
73