Well they certainly blow the V900s out of the water. Obvious conclusion number 1. But one minor problem. They are only semi-closed cans. But that is a small price to pay for this type of quality. I am listening to the Tool album Lateralus. Ticks and Leeches is the song. On the V900s the bass was muddy and very distorded. On the w100s the bass is accurate and balanced. The mids and highs are clear. I suspect 80 hours of burn in will make these cans even more enjoyable.
they are fully closed headphones, they just don't attenuate much outside noise. they really are great cans though and the more you burn them in, they better they sound. accoustic guitar is absolutely amazing on them.