This glass on both sides of my Z1 compact it has fallen down. The glass on the back is splintered here and of course irritates me that. However, it is just glass, and it is not indestructible, but a protection for orginalen surfaces. Until the accident it had no discernible scratches and it feels even better to than the normal surface of Z1c
The defective glass I could without problems stand out in one piece, from the back and the task of protecting my phone has fulfilled perfectly! I'm a new order and hope that I get my phones do not drop!
The only drawback in my eyes: The fairly high price! However, spare parts or repair cost of the smartphone much more!