Ah... I think my ears are spoiled by ER4S, I just bought a HE400i, while the sound is more full-bodied (the advantage of over-ear I guess), it is nowhere near ER4s clarity.
Fellow ER4 owners, do you have over-ear recommendations, that don't make you wanna throw them away after 10 minutes...
Stax SR-009 or HE1000.