The difference in resolution was very obvious to both of us.
The K1000 are fine with easy listening music like Diana Krall and Jane Monheit. But they simply fell on their face with any complex symphony and rock.
It is good
Actually we thought the O2 fared better with rock as well
I wrote about the bass in the first post, which makes a big difference when listening to rock. I don't think the K1000 reproduces a drum kit or electric bass faithfully. And my friend only listens to classic rock and jazz.
We did not use a subwoofer with the K1000. It simply wouldn't work for my friend. He might as well listen to his speakers, but risks the chance of waking up his wife or kid. We treated both as headphones.