My 1p2's are paired with the HM-901 (balanced amp card), i've spent a little bit more time listening to them. I found that the comply foam tips + wax guard helps a lot with the sibilance so i'll be sticking with them for now. I guess it also comes down to how the music was mastered, if it was badly mastered and already exhibits sibilance then the 1p2 will just accentuate it even further.
So compared to my Roxannes, they definitely sound less claustrophobic and the mids are more laid back. Bass doesn't hit as hard as the Rox, but they still have great sub-bass and thump. Sound staging is slightly wider on the 1p2, but 3D imaging I still find the Rox better. The Rox I find, still has the uncanny ability to pick out even the most minute sounds, it resolves extremely well. Both the Rox and 1p2 have completely different sound signatures, the Rox are darker and immersive, the music really wraps around your head and the bass slams hard. The 1p2 are airy, laid back and gives the music a great sense of space. Perhaps, if I had listened to the 1p2 with uber cable, my opinions on the 1p2 may change, but for $1300, the cost is unjustifiable.
In terms of size, the 1p2 are slightly smaller and lighter than the Rox. Despite being smaller, they do exhibit terrible microphonics with the silver/gold cable. Its pretty stiff, which translates to hearing almost every knock and movement of the cable - not a very good choice while walking about, I might consider an after market cable just to reduce microphonics. The Rox while much larger, has very little microphonics since the cable is much softer and rather flexible.
Has anyone ran the 1p2 on balanced audio? How much do they benefit from it? Thanks!