Well my ATH-M50 arrived today, and I've barely been able to take them off!! I braced myself to be underwhelmed after all the criticism from many individuals, just hoping they'd sound cleaner and more neutral than my current cheapo Senheissers (eh150).
Well holy crap. I am blown away. I just can't believe how good these sound. They look and feel solid, such high quality. They're very comfy, though my left ear is getting a tad sore after prolonged wear. But the sound. Wow. Everything just sounds - clean. Not muffled, not shiny. A tad warm, but mostly just sounds like it "should". Mids that normally irritate me with other headphones, leading me to EQ them down, sound warm and inviting. Base is solid, definitely not overwhelming, and definitely not boomy at all - yet full, without being rich. Highs are clean but not piercing. So far just been listening without much EQing, maybe turning the mids down a tad and pulling the base up a notch, but really, my music finally sounds "right".
Might write a lay-person's review, but I'd probably just be echoing the dozens of others out there - these are good, solid, clean neutral headphones that just sound great, feel comfy, and ooze quality. So happy with this purchase!!