I always had them on all my devices, main reasons are phones on pocket and my kids, I've used different cling on protectors, until I got my galaxy note where I got a spigen ultra clear and loved it, so I have one on my nexus 10 and my wife's nexus 7, the best way to apply without anything left under is to align the screen protector secure it with painters tape over the outside , clean the screen really good, fold the protector back, and before removing the backside film, put painters tape all across covering the screen, and then pull the edges of tape and the back film while pressing the screen protector and sliding down as you pull the tape/back film together towards you until you apply the protector fully and squeegee the bubbles out, you will end up with a flawless screen, because the tape will pull all particles from screen.
Sent from my Nexus 10 using XDA Premium HD app