I still put a screen protector on all the phones on my account. Though they're not as necessary as they were a few years ago, the screens can still get scratched. The newer protectors from Zagg and Skinomi have pretty much removed that "orange peel" effect of the early ones. They also really reduce the finger smudge / fingerprint on the screens and I think help with the touch function (the naked glass is too slick IMO).
I use the Skinomi protector on my MAXX HD and RAZR M and love it. Plus, you can request a replacement directly from their website, they send you a replacement within a few days, no questions asked, no extra charge. So quick and easy. On the S3, I bought an OtterBox Commuter case and it comes with it's on screen protector... more rigid and smoother than the Skinomi...It doesn't help as much with fingerprints but seems to be working well. The user of the S3, my younger sister, is a bit of a klutz and the case and screen protector seem to be doing it's job so far.