So my pair arrived from Germany on Saturday and I've probably put a good 20 hours on them over the last two days. I have to admit, I really like these. The best way I can describe them will sound like Im ragging on 'em, but I dont mean it that way at all.
Basically they have similar tonality to the Audeze LCD-X, so if you start with the X and then take away everything that makes that headphone special and worth the full $1500, then what you're left with are the HE400s. Both are very easy to listen to, but the 400s dont dig quite as deep and their top end isn't nearly as refined. The sound stage isn't small, per se, but it lacks that 3D space that the Audezes have. The mids are very clean and in balance, but they lack refinement, as well. Overall they are not as detailed or transparent as the Xs, but these drivers (and it's one reason why I LOVE planars) aren't veiled at all. Another headphone I had in recently was the Sennheiser HD700s which, even though they were over twice the price, had a very obvious veil that I could never get past. The Xs give you a window that lets you see DEEP into the music, to a greater degree than the 400s, but these budget planars avoid the veil that some dynamic drivers possess.
I'm also very happy with the comfort. I did go ahead and upgrade to the velour pads, and even though they aren't nearly as nice as the T1s velour pads, they are certainly more comfy than the pleather ones that came stock. As far as weight, these feel about like the T1s on my head...not quite as comfortable, but I can wear these for hours at a time. The clamp is just about perfect and the weight distribution is appreciated.
I actually think these are still a very good value even at their original MSRP of $399. I paid $280 shipped from the homeland, so I am very pleased with the value here. If you're on a budget but still want to enjoy that beautiful planar sound, like Milford said, these are your headphones. You can still find these around, but I don't think they're in production anymore. I think Jan still may have some in stock, so that's one place you can probably still find a pair.