I tend to use my phones naked. This past year, though, for resale reasons (and extra grip) I started using invisible shield to keep scratches down. While the rear film will be a given (to keep scratches down), how necessary is a screen protector on these newest models? They talk about how hard the iPhone glass is, but I recall many people having scratch issues on their iPhone 6 models. Was this fixed for the 6s? I wouldn't question it normally, but the slightest nick to the edge of the zagg glass leads to cracks... Which I'm sure will be worse with force touch. So, is it even worth paying for a screen protector?