Hi all, Getting back into IEM / portable closed back since I need isolation for work now (I originally used TOTL earbuds). Looking for what would essentially be an upgrade over the etymotic ER4-XR or RE-400 (been awhile since I've had these). Was wondering what my options were before I end up...

Looking for an upgrade (or side-grade) over the ATH-M50x for my little brother. Main points in my decision: Build: It has to be tough. He's broken the old ATH-M50s where the hinge is... Tends to throw it around... Portability: He takes it back and forth between locations, so maybe something...