My brand new 2015-issue blue silicone case peeled off the bottom left hand corner immediately after I put it on my iPhone 6S Plus for the very first time! In contrast, my old 2014-issue blue silicone case has been through hell and back on my previous iPhone 6, and shows no issues at all. It's still going strong with the new owner...
The new silicone cases seem a lot more fragile than the old version.
The new silicone cases seem a lot more fragile than the old version.