We got the Verizon ones installed on our phones day 1. My fiancé's N3 developed a bubble a few days later, which was deemed a bad install and replaced at no charge. A few weeks have gone by now and while sitting one night, a huge bubble developed on the bottom edge, like the glue let loose. I have the M8 and mine developed a small bubble in the top left corner, but not enough to bother replacing (yet?). All 3 were installed by the VZW reps, so I don't know if this is an issue with the protectors, or just shoddy installs. It looked like the reps were pretty meticulous with the prep and insuring the screens were cleaned, so I'm leaning towards bad glue or another product defect inherent in their design. The protectors looked perfect right after the installs and the bubbles didn't show up until days/weeks later.
While we absolutely love glass protectors over film, I will say I won't be getting any more VZW branded protectors.