Well with some brain burn-in, I am certainly liking these 400i more. But, man, they clamp tight. Haven't tried to stretch them out at all to see if that would help, but 3 hour sessions are out of the question, at least until/if I get more used to them.
Now, my biggest previous complaint, the bass...I may be beginning to hear what people mean with they talk about texture and clarity. The bass on them is gorgeous. I still contend there is no "rumble". Stumbled across K.Flay on Spotify, and music like that just does not seem fun at all on the 400i to me.
On the other hand, the intro to Linda Ronstadt's cover of Hurt's So Bad, especially when she comes in with the vocals, is simply magical on the 400i to my ears. I very much prefer the mids and highs on these over the HP150.
Maybe I'll start a thread and ask folks if they ever find one headphone that does it all for them, one that they never want to swap out for a certain song, or type of music.