Thanks, I suspect I will be ordering my 560 today, just making up my mind about also keeping the HP50, or selling it. I will keep the HP50 for a time to compare directly as I think such a comparison is needed. Like me, I think there are other users out there with a decent performing mid-tier can who wonder if spending double nets you any significant gain in sound quality (different sound signatures aside as much as possible). I will then post a review of my subjective experience here in this thread. Thanks again.
Having the K612 as my current reference headphone... We basically are on the same boat