HiFiMan HE-560 V2

Got my HE560V4 for couple of weeks now, not sure if it is the same headphone as V2 or V3. Some guys at chinese forum saying these are the bestest HE560 in the lineup, I have not heard any other HE560 to confirm that.
Chain: Pi2AES>BF2>BHA-1>headphone
Some brief impressions: Big stage with great clarity, maybe fake resolution due to bright signature, but not missing out on information compared to HD650 and Atticus. Some sibilance issues out of the box which seem to improve after some burn in(150hr recommended on manual), still peaky but bearable. @FlySweep The HE560V4 can slam as hard as Atticus, but do require some power. On my gain modded BHA-1, I need to switch on high gain for them to slam, on low gain they are soft sounding, but still the bass is not as hefty/meaty as dynamics. Blu-tack mod helps with the heftyness of HE560V4. Imaging was weird and diffuse initially, which is a big nono with the big headstage. However after some fiddling I suspect the driver has reversed absolute polarity, as the image became much more precise after I switched the phase reverse function on my BF2. Timbre not as natural as dynamics, but with the spaceiousness and clarity, I think they are sidegrade to my HD650 and Atticus and more versatile.

SW51+ is nono for this headphone, guess there isn't enough current.

Oh yeah, I saw this post https://imgur.com/a/WghAM and decided to make my own shelf liner to stick in front of the driver.
Absolutely would not recommend, I did this with blutack mod thinking front damping is gonna tame the treble but no, the treble became unbearable after this and I spent 2 days trying to retame the treble.
Front damping with even 1ply TP sucks out some macro and muffled the sound, and any type of rear damping shrinks the stage, I'm leaving my unit with just blu-tack mod now.

Some measurement comparing to my modded HD650 and Atticus. I lost my UMIK-1 measuring cardbox so I made another cardbox(0 damping) using a modmic. Take it with a huge grain of salt.