[buke9]

I'd say go with the x2, they have a very fun sound quality for music listening with huge soundstage which will most likely suit you better than the other options coming from a pair of m100s. Although they are v-shaped, they are not nearly as dramatically v-shaped as you will hear from many other people. I am not that into bass and the amount of bass in a headphone is irrelevant to me unless it makes an audible difference in the clarity, this was not a problem for me with the x2 and most people who say it has way too much bass are probably coming from headphones with nonexistent bass. If you're older than 40 the dt990 would probably be good since you won't be able to hear the ear destroying highs especially on the dt990 premium which has more treble than the dt990 pro.

Wow the first agest post I have seen on Head-Fi awesome. I'm over 50 and find the 990's bright.

 

[EMAudio]

Wow the first agest post I have seen on Head-Fi awesome. I'm over 50 and find the 990's bright.

I stand corrected, they're still bright. might sound good for someone with hearing problems then I guess.

 

[buke9]

I stand corrected, they're still bright. might sound good for someone with hearing problems then I guess.

I like bright but they are too much for me. Sorry had to give you a bit of a dig for the comment; )

 

[EMAudio]

I like bright but they are too much for me. Sorry had to give you a bit of a dig for the comment; )

Me as well, love highs unless they're to the point of being painful

 

[Deoee]

The X2 are great but I can not compare them to either of your other choices.

They have a huge soundstage which makes gaming and live music a joy.
Bass is prominent and very potent for open cans! The treble is elevated and can be sharp at times but it's nothing to be annoyed of. Comfort for such huge headphones is EXCELLENT.

Compared to HD598 the music feels very "in your face" and present and its just fun listening to.

I'd totally give them a try.