I own both the Hi 2050 and the MH463. The Somics audio quality beats the 2050s. Comfort goes to the Hi 2050s without question. When you put Turtle Beach pads on the MH463, comfort between the two becomes a lot closer together, with the 2050s still winning because they're lighter.
I have no idea what mods I can do to get the Hi 2050s to sound like what I think they can sound. They need to be more open. But they lack bass in quantity and impact, despite the fairly thick cloth lining inside. I feel like no matter what is done to the 2050s, they'll need EQing.
Conversely, the main goal of the MH463s is just to make them more comfortable. I love the audio quality, but it is the least comfortable pair of headphones (stock) I've ever worn. I feel like it can be modified extensively (and successfully) for comfort, but it will require time, patience, and probably one or two extra pairs.