I've not bothered with screen protectors for a while. The truth is that one day I realized I was putting up with a horrible screen experience so that one of my kids to get my scratch-free handset at some point down the line.
My iPhone 5's screen goes commando! That said, I do protect the rest of the phone with a G-Form case. Without that there would only be a few random parts of my iPhone left!
I've just taken a look at my iPhone 5 -- which I've had for about eight months -- and the screen is in pretty good condition. There are a couple of light scratches, but these are hardly visible, and to be honest I'm not even sure they are scratches. The screen could just need a good clean!
While I'm not going to carry out a scratch test, the folks at iFixit have. Here's a cool video or MJ and her daughter Ellie putting an iPhone 5 through its paces. It's both adorable and painful to watch!
All in all, the iPhone 5 seems pretty scratch-resistant to me!