It probably depends on the headphone in question more than anything, though I can safely say that for gaming alone (no music listening), you're well past the point of diminishing returns at that level. I probably crossed that point already when using a vintage Stax Lambda setup for gaming, and those only run for about $250-400 these days with a transformer box.
If you really want a flagship headphone that's competent at gaming, Stax in general and the HD800 would be the safe bets. I don't know as much about the others (in part due to focusing on Stax for the expensive stuff), but the K1000's design feature of fanning out in front of your ears would probably destroy the effectiveness of HRTF-based mixing technologies like CMSS-3D Headphone, Dolby Headphone, etc.