Could you describe what exactly is the sound you can't stand when your K701 plays rock/metal?
Have you heard the SR80i? 
well i listen mostly to guitar driven rock/metal and instrumentals. I feel that the distorted guitar sound sounds too clean with my K701. The sound also feels "distant".
But for other genres like jazz,acoustic,classical,pop, etc. I love my K701 to death

No. i haven't heard any Grado headphone but I read that they excel in rock/metal so I am considering them. Well I mainly use my D1100 for my rock/metal tracks but I find them to have too much bass for my taste and the mids is quite distant.