I own a pair of HD650's (silver drivers) they are the best things I've ever heard, super comfortable (I've had them on all day before and forget they're on) these are the only pair of high end headphones I've owned so I don't have much else to go by except IEM's but I would say the 650's are...
I own a G400 (no prediction) a WMO and a G9. I currently use the G400 as it's technically the best sensor on a mouse and I agree it's flawless, especially at high speeds, but the mouse I owned the most with on FPS was the G9 because of the shape with it's precision grip.
The ideal mouse for me...