[VitaX]

Which do you think would be more comfortable and offer better sound quality for listening to rock music such as: Alice in Chains, Buckethead, Chevelle, Led Zeppelin, Mother Love Bone, Mudhoney, Neil Young, Nine Inch Nails, Nirvana, The Offspring, Pearl Jam, Rage Against The Machine, Red Hot Chili Peppers, Screaming Trees, The Smashing Pumpkins, Soundgarden, Tool, etc... I think with that list, you probably have an idea of what I listen to. After looking around on here and reading different posts and threads, I've come to the conclusion that these are probably my two main options.
 
Is the issue with the cracking on the Sennheiser headphones really taken care of now? I currently have some HD 555s and they have cracked above the ears on both sides of the headphone and didn't really want to spend more money on another product from them if this issue is still occurring. However these are pretty damn comfortable headphones, I can wear these for many hours without feeling any pressure on my ears. Can the same be said for products from Grado?
 
One last thing I'm wondering about is, what amplifier would you recommend for these two headphones? I've heard the MS2s tend to like a tube amplifier.

 

[whoelse]

I have both, MS2i is very special and I like it a lot and when I got hold of HD-650 I like it even more. Maybe in love is the correct word with the HD-650. I can also listen to it for long long hour sometime forgetting I am wearing it and simply refuse to remove it.
 
I am using Mini-RA Amp which is very high current, it drive both MS2i and HD-650 beautifully. Source from Teclast T51 Line out.