I really like these IEMs.  The casing is almost indestructible, they have detachable cables, and the sound is great and very clear for dynamic drivers.   The casing is made from Zirconium.  They're advertised as being related to diamond, which isn't true and a little too much marketing speak, they are indeed very very hard.     The sound is a little bit V-shaped with too much emphasis on the bass & treble.  It can be fixed through the use of an equalizer, but it'd be nice if it were more neutral out of the box.  But the clarity is fantastic...

Fit was an issue, these are HUGE!  Not for small ears, and getting good seal is important to get the best out of them.  Walking would break the seal with every step, even with foam tips.  You really have to push them in to get them to stick, and even then they'd work their way out.   The cable also has a bendable bit embedded in them to make a U for wearing them over the ears.  It was a nice feature but made putting them in your pocket difficult and the cable got tangled very easily.     Also, the bass driver in one of the earbuds died after...