I've had mine for over a year, and it's held up very well. It's interesting that the glass back has fared better than my plastic iPhone 5C, metal iPhone 7, and metal HTC M8 did. I counted close to 30 nicks and dents on the M8, and the 5C was just a mess despite being babied.
The only failure was the USB C port, but HTC fixed that for free despite being out of warranty. Performance, camera, and audio are still awesome. Faster than our son's iPhone 8 Plus or my friend's iPhone X.
The gorgeous screen was unexpected. I use the U11 side by side with a Note 8 at work, and the U11 LCD is just as vivid as the Note 8 AMOLED, slightly brighter, and sharper. Amazing job.