mine did arrive today, and I put it on. The plastic backing on the protector is a fail, as the pull tab pulled out from between the protector and the plastic pretty much right away, but I was still able to remove the protector without issue.
Installation went pretty smoothly, though I have a couple tiny, narrow lines along the very edges of the screen on both sides that I couldn't push out with the microfiber after installation. I could rub them away with the cloth, but they would return right away. I'll see if they go away, hopefully they do.
Cinder is a crap company for sure, but the product is indeed pretty nice. 1+ year in I finally have my final protection for the phone, the Cinder protector and a non-force Power Support Air Jacket. On that note the protector is an absolute perfect fit with the Air Jacket. I was worried based on how you have to install the phone in the Air Jacket that even if the protector fit with the phone, trying to install the phone in the case with the protector on would be a problem but it doesn't seem to be the case, phone slid/snapped into place without issue like always.
Some pics:
You can see the little white line along the edge on the lower corners of the screen, hopefully they go away: