I've been somewhat obsessed with the Hifiman line lately. Still trying to get a sense as to whether or not my future ECBA will drive the HE-6's and am also feeling tempted to get the 400's, since they fall below the arbitrary "too much $$$" line I've set for myself until I finish school. I feel like they'd make decent "walking around in the park looking like a dork" headphones, as they can apparently be driven well off portable amps.
I'll probably send my HE-500's back this week. I just need the time to take them over to UPS since I'll never be home for a pickup.