Pros: the very good porta-pro amps, ear-clip system, simple and very functional design
Cons: typical repairs every 3 years: wire contact gone
Excellent opened overheads for everyday use with the typical sound brilliance of Porta Pros with a little less of bass overboost (which is positive) due to being not that pushed on the ears.
There are few things in the world that need no improving. KSC-35 almost fit in there - if only the wire ends in the phones were attached a better way so I wouldn't have to get them fixed every approx 3 years. Replacable molitan covers can be cheapely purchased (only I always buy set of three pairs and lose the other two until I need them, so one pair set would be better).
I can wear these headphones all day (and I do so) in the office without actually feeling them on my ears. When I am carrying them, I appreciate the click-in mechanism which prevents them to brake (the amps only get detached from the ear clips, without breaking up).
Cable could be longer to reach my desktop PC under my desk, but that's solvable by extending cable - which but adds extra contacts with all the negative affects to the audio quality, so savnig on crappy cheap extension audio cable is not advisable!
But of course, there are far from studio quality. Well I am glad for that as I can hear basses even on low volume and don't have to set volume to very loud...
For top sound quality listening in not too noisy environment, I'd pick up AKG-240 which I had for a few months for testing, also very simple functional (studio based) design, and the audio is crystal-clear. The problem is you won't be willing to listen to 128kbit MP3s, as their quality is awful for the headphones... But at work I'd always pick KSC/35, being open I can hear colleagues talking to me without taking them off etc.