Haha, I understand the benefits of purchasing used (value, burnt-in, etc).
But I'd would prefer not to, as I like the experience of unboxing the item.
I've read that the M50 while extremely good, has powerful bass... and I'm guessing it can overpower my music, what I originally wanted was something similar to the SR60i, that works well with rhythm guitar without too much bass. I've still gotta do some research on Superlux.
In that case...
Fostex T50rp
http://www.bhphotovideo.com/c/product/281431-REG/Fostex_T50_RP_T50RP_Studio_Headphones.html
I've heard the odd Superlux headphones over the years and I was never impressed (not even enough to remember the model numbers). But you are missing out on getting much better gear for less $$$. And basically all the stuff I've sold over the years has been basically like-new.