I've owned ATH-m50x, ATH-m40x, and HE350 on a Schiit stack. I've bought and returned HE560s because they weren't worth the price and the sound signature was too thin. I've never heard another Fostex pair of headphones, so I cannot compare to the T50RPs with or without mods.All I can say is that these cans are the best cans I've ever heard, except for maybe the HE1000 that I demoed at a trade show. They are so damn thick, rich, and precise! Bass is really present, smooth, and detailed. Vocals aren't as forward as something like a m40x, but are extremely filled out and pleasant to listen to. Soundstage isn't very wide, but the placement is very precise. Gaming in these is really immersive.They are also very comfortable out of the box. I tend to replace my Audio Technica gear with Brainwavz hybrid or velour just for comfort. But the pleather pads are very nice and I haven't felt the need to experiment. Build quality is beautiful and feels robust. The 3.5mm jack is super convenient. The cable that comes with it is high quality and sleeved. If I had a balanced system I'd spring for the four pole balanced cable.I hear something in the Schiit Magni range is the lowest power gear you should use, because they're pretty power hungry. Word on the street is that if you try running it off say an iphone or even a Dragon Fly Red, you won't get the full sound signature, even if they are driven to loud volumes. These are not portable headphones.If you're in the price range and have an amp that can power them, it's a no-brainer.Update 1/19/2019: Unfortunately I have to take off two stars because the left ear cup’s hinge has developed a persistent creaking any time I move my head or jaw. That’s a pretty serious flaw for a headphone of this price tier, and completely ruins the user experience.