Just as a passing comment, as I was looking over this thread due to my interest in the Cardas replacement cable.. I must say, I've *feared* that the HD-600's cables were flimsy and could be tugged out easily or otherwise malaligned..
*But* under the considerable use (some of which would make some here cringe I'm sure) I've given them, I've not had any issues with the stock cables. They haven't come loose on me, etc. I wish I had a better way of controlling the exact cable legnth than a twist-tie, but that's just a minor gripe that can be easily fixed. That way I don't do something stupid like trip over them or something.
The -one- issue I've had with the HD-600s is one of the headband clips that holds the padding in place came off and got lost, so now I gotta adjust the padding occassionally.