[dablues]

I agree about the Crossfade LP, at least in terms of durability. Pretty dark/bassy, though. But very well made.

My new-to-me Beyerdynamic DT1350 feel like they could withstand a LOT of punishment, and they're pretty neutral as well.

 

[egokun]

HD-25's or the Amperiors.  They are built like tanks. 

Maybe not the sound you're looking for, but as far as durability goes, James Bond would choose the HD25

 

[ChriG]

Ultrasones Pro series is really durable headphones. Not very neutal though.

 

[Koolpep]

From my experience in terms of durability:

Ultrasone Pro 750
Beyerdynamic DT880 Premium
Sennheiser HD25-1 (all variants)
Beyerdynamic T50p/DT1350
Superlux HD668b, HD661

Cheers,
K