Whitestone for ease of use install. Techmatte amFilm is more DIY (less friendly install), but better customer service. When my installation tray broke during install, they offered a one time warranty refund on my purchase (ie. got the protectors free). Works great, cheaper than Whitestone and you get 2 protectors.
amFilm tray is flimsy and wouldn't recommend using that too install. You're better off DIY.
I still need to find time to remove the cured protector and reapply it. But no complaints on the protector itself.