I have the M50s "white box" and, to my ears, bass is not at all overempowered, nor are the mids quite so recessed (a little bit, not as much as I've read here). They're actually pretty great headphones, and I think most flaming comes from people who has not actually heard them, just like they were getting undeserved hype, now they're getting undeserved hate.
Their greatest flaw is the harsh highs IMO, but it's not such a problem. I actually find it suprising that people finds the bass overemphasized, sure it's strong, but all my other headphones have even stronger bass.
I guess every ear is absolutely different.
I owned the M50's. Not of my liking.
Still, as a starter headphone is not bad.