@fiveamp
This doesn't quite answer your question, but I've owned B&O H6, H4 and currently
B&W P7 and Sennheiser HD600.
In my opinion....
They got off to a slow start for me, but I'd rate the Senns as the one I'd stay with, if I did stay with just one of those.
The B&O are a bit more spacious sounding, more comfortable (I agree about the glasses, but even so they are OK cumfy for me) but not as well or as naturally resolved and have sloped off top end extension, less 'sparkle'. They've a notably natural midrange tonality. The bass on the B&O is probably the best I have heard from a headphone, it goes really deep, taut and powerful (but not in an unnaturally elevated or boosted way, it's just there when the music asks for it). But I'm not hugely into bass.
The B&W don't seem to suit my tastes, which are mainly classical music oriented. I'm not quite sure what it is about them, but I'd rather listen to any of the others. They do much better on Dream Theater than Debussy.
So, to sum up I'm a rather reluctant Sennheiser HD600 fanboy, for the options you specify. And I think they are a very good headphone. I'm not keen on the earpads, but they do seem to be settling into shape with use. I've a pair of Dekoni sheepskin pads on order for them.
I've rather more cans than that, though, including the currently and understandably popular Hifiman Sundara.
My preference overall would probably be Monolith M1060 planars. Listening atm; gorgeous. Spacious and immersive, they put me into the music in a very entertaining and convincing way.
But if you need closed back, then Sennheiser HD 600 get a strong thumbs up from me. For me, they do need peaks at 3.5khz and 5khz taken care of (I find them intrusively bright otherwise) and a hefty bass lift starting at +3db @ 80hz, rising to +8db @ 35hz.
Keep an eye on the Sennheiser website, there will probably be an offer closer to £200 coming along sometime soon.