In my sig, currently using the Matrix. And psycho acoustic burn in yes, just like with every can/speaker.
I have heard speakers costing over 100k and dozens from 5 to 75k and have speakers costing over 10k in my main. (Yes I'm a speaker guy mostly). My cheapest speakers are 1200 retail and in my garage system (I have 7 systems around the house/yard) and yes I think even they trump any headphones (not that I've heard them all of course) and I do like headphones, but they just can't compare to speakers, especially exceptional speakers imo. Thus why I haven't felt the need to spend more than $250 on cans before...but maybe I shouldn't have waited.
Lower mids already bugging me less...and these are not at all harsh even at high volumes with music that can make you wince on poor setups. There is sibilance, but the kind that is just always there no matter what the setup.