I have just a 1080 video card, running my Reverb (1st gen) and my FR dips well below 60 at busy bases. The unit I have now is a replacement under warranty (which was a pain to arrange with HPs support, but when I finally got through to the right dept/person, the exchange went smoothly). I dont use the earphones - still use my headset with mic, over the top of the Reverb. My youngest son was visiting and wanted to try it out, we found the new headset has a non-functional earphone. Cant remember if right or left, but I don't need it anyway, and the warranty is over now besides.
I wish the sweet spot was larger - resolution great as you say, but only in the smallish sweet spot. Everything outside of this is fuzzy or unfocused. You learn to look directly at anything you need good clarity for.