I'm getting a bug to buy these, tell me why not..

[Happy Camper]

Hand wash/air dry.

Mine are on my head as I type.

Looking at your gear says you are familiar with quality sound. FR & such are marketing gimmicks. No way a hp will give you sub bass in the 10~ range. Not too many subs will get that low. Throwing sub freq. sweeps at them will give you an idea of how accurate they stay until the bass starts to fall apart. If no source gives more than 22k (human threshold), what does having an upper range twice as high do to make it sound better?

I agree with you about your amp being a good match. Others are the Heed Canamp, Dark Voice 336SE, Millet Hybrid, Woo 6 maxxed, Singlepower Extreme (certified used), Beta 22, Bijou. If going full tube, the extra spent under the hood (quality parts) is critical to getting everything out of the headphone and perform with impedance mismatches if using multiple hps. I've been able to tuberoll some bass and an even larger headscape to the presentation.