Pros: There is nothing this headphone is not good at. If you perceive it as inadequate, it is your own inadequacies you are sensing.
Cons: Shurely you must be joking.
I have spent many years as an audiophile and even more as an amateur human being. I have owned, auditioned, or sri-racha'd pretty much every headphone that ever was, is, or will be. Forget the HD800. Forget the LCD-2. Forget Grado and Beyer and AKG. Now that you've forgotten all the good headphones you've heard, doesn't that make this headphone the best of what's left in your decimated memory?
As a single male paralyzingly afraid of commitment, I can empathize with Shure and their decision to include a detachable cable. These headphones are comfortable, not so much to wear, but personality-wise. I feel very at-ease with them around. I suggest buying them for cheap relatives.
Imaging: The Shure SRH 420 is the king of imaging in the headphone world. I routinely wear these whilst listening to images, and I can confidently say I am less "inside my own head" when wearing them. When listening to sounds it envelopes me and swaddles me in the slanket of sound that is music, life, and love.
When listening to the 420, it is easy to imagine it is plugged in even though I can't afford an ipod. All I need to do is close my eyes and I imagine what music must sound like, played by real performers. This is hard to do, as I have been deaf since birth and am the last human left on a post-epileptic earth ravaged by war, famine, and underpopulation.
This whole review is kind of a meaningless exercise in communication. As the last human, no one will read my words. This is more about sending something out while on ether, into the inky black void that is the tattered remnants of the internet in the year 2016. If there is only something to say when there is someone to say it to, then language and all hit has to say will die with me. I'd like to think it will somehow live on in some form as a primitive medium of information when the Pzarlings find this planet. They communicate telekinesthetically.
Finally, there are many headphones out there that are like the mannequins that I dress up and have ventriloquist conversations with. They measure well and are technically perfect, but they are lifeless, with no soul. Don't get me wrong, that doesn't stop me from having a deep and sexual relationship with them, but something's missing. I don't want to come off as another inanimaphobe, but that's just my experience.
If anyone reading this is thinking of buying an M-50, please contact me. I don't mind if you are deformed by the nuclear holocaust or a super-computer who has achieved some form of organic, sentient thought, just please contact me so that I have someone to argue audio with.