>>106981897
I haven't used the M50X. I did own the M40X and about 5 other sets of "home stereo" headphones from Sony, Audio Technica, AKG, and Sennheiser. When it comes to the sound the 650s are endgame for me. I absolutely love them.

Having said that, I know this is heresy but if you only use your headphones with a PC source and want to try a cheap comfort solution you can also get some aftermarket memory foam earpads (I had some Brainwavz that made my M40X very comfy - see pic for comparison of Brainwavz vs. stock pads - but they also made the sound worse) and then use digital EQ (like EqualizerAPO if you're on Windows) to fix up the sound as much as possible including getting rid of any peaks. I don't really recommend doing this if you move your headphones between different un-EQ sources like PC/mobile/console because of how the aftermarket pads can fuck the sound. You may or may not be happy with the result but it's a much cheaper attempt than buying a new expensive set of headphones that you might not like that much.