The Audio Technica M50s are often touted as the best value for money headphones on the market, I disagree, they're not good as general purpose headphones and they're certainly not "monitors". They're an excellent alternative to other over-bassy headphones like Dr Dre Beats and I understand why people like them but they can make human speech sound annoying and unrealistic, particularly the sound of Don Draper's voice for some reason.
The MDR7506's are cheaper and more versatile, only buy the M50s if overpowering bass is your #1 priority.
I disagree, I reckon the M50X's are the best headphones and are perfect.