I just got mine a few hours ago and I've got mixed emotions so far (still burning them in). Coming from Sennheiser HD448s, the K167s have more bass, but like Tyll said, it seems a little awkwardly emphasized. The HD448s have a flat(er) response which I prefer, however I must say that I like the slightly recessed mids in these cans. The overall detail is a lot better, however the HD448s have much clearer highs which aren't as harsh and also have better soundstage (due to the open design I guess). The k167s still have great soundstage, it's just that it's slightly better in the HD448s.
Comfort wise I'm extremely pleased, and that's coming from a person with big ears. Of course the noise cancellation is uncomparable to hd448s, much, much better.
Overall I'm happy with them, I'm glad I bought these over the Sennheiser HD558s I was looking at (I've listened to them briefly as well). If memory serves me right, I had a similar issue with the highs being too harsh in the HD448s when I first got them, but then they seemed to adjust after several hours. Hopefully the same happens in the k167s. I'll report back after I've played several hours of music with them and mention any differences.
Overall I think the k167s are great bang for buck.
(btw I listen to rap/reggae/dancehall mostly).
EDIT: The cable quality is HEAPS better as well, I'm not a fan of sennheiser cables
Edited by Aleckazee - 5/15/13 at 4:38am