Well the 600 ohm version of the DT880's is the best out of all the DT880's. It has more bass than the recessed bass of the 2003 DT880's and less harsh highs than DT880 '03 as well.
Impressions from me and others (vs. other DT880's and other headphones):
If you got good amplification, the DT880/600 are a no brainer vs. the K701, HD650 and HD600 tbh.
I'm hoping to find something smooth, definitely.