Personally if I were you I would get some really good audiophile, open backed headphones and then buy a gaming sound card so you can get a much better DAC/AMP and then some cool DSP's like virtual surround to make the headphone better for gaming and music.
I have Sennheiser Amperiors and with a surround sound DSP the sound stage widens and I can accurately pin point positions. The sound quality is amazing clear and potent. It works very well for gaming even though that is not its intention. Get a headphone with a much bigger sound stage to begin with like a Sennheiser HD 598, 600 or 650 and then you will have even better results then what I'm getting.
The major problem is power with big audiophile headphones so getting a sound card with an amp is key, whether an internal or external one. Asus Xonar Essence STX would be a nice pairing. On Ebay the card can be had for around $120.
No doubt a pure high end headphone will beat the gaming headphone in music. All the other genres can be had as well through DSP's that the gaming headphone most likely uses.