I don't feel harshness or distortion of the mids at higher volume and I don't listen to bass heavy music. I listen to 90% jazz, 5% R&B, 5% classical. I'm running it with the Singlepower Extreme Platinum tube amps. Some say that the mids are a little recessed but I think it depends on your musical orientation. I prefer the audible illusion of watching them play rather than playing with them.
@dalethorn - I'm looking forward to it
.
I will take another look at those 880/600 ohms, hopefully soon as there are more people who prefer the 600 to the 250, this goes on my to do list, lol. The list gets even longer.