For the price, the M-50s are excellent headphones. I use them weekly in professional recording sessions and they hold up well. I think that's a good situation to use them in: where you need high quality personal monitoring and you need multiple pairs with an eye on the price.
If you are springing for a single pair of high-end headphones, maybe you should go for the Sennheiser HD-650 or something similar. They are higher fidelity than the M50s but are also over 5x the price.
If you are springing for a single pair of high-end headphones, maybe you should go for the Sennheiser HD-650 or something similar. They are higher fidelity than the M50s but are also over 5x the price.