What would you consider to be better than the HD600 at that price point?
IMO there isn't really anything better under $1000... Apart from the HE500 perhaps. But of course its just a matter of taste and what you want from a headphone. There are no surprises with the Senn's, just a very natural tone with a realistic image and airy soundstage. They are probably the most versatile hp going. Nothing sounds bad on them!