Yes I'm very happy with these cans. Even witht the stock cable and not burnt in they sound fantastic. Certainly an upgrade from my Beyerdynamic T51.
The Fiio X5ii seems to drive them better than the HTC headphone port. The X5ii is a great match, in fact, because it is a little on the bright side, to v1s somewhat relaxed sound signature. I found the Beyerdynamic T51 a terrible match, as it seems a bit treble oriented, with the X5ii it was screetchy and hurt my ears if i turned it up load enough to hear the vocals and bass. The T51 was ok with the HTC 10 where I could apply the equaliser, but still not to compare with H6.
I feel like I've rediscovered my X5ii, listening to DSD and FLAC files just sounds fantastic with the H6. I don't even care about the lack of equaliser on hi res audio, because the feels just perfect for my taste, as is. From the HTC 10 headphone port, it sounds a little enclosed and less airy, but still great detail, I was even listening to music with the eq turned off, which I never normally do.
Edit: has anybody tried this cable?
http://www.oehlbach.com/en/for-headphones/cables/xxl®-i-jack-35
Its on Amazon.de for €46