My reply is not specifically what you're looking for, but is another viewpoint.
For over 2 years I carried a Nexus One with me wherever I went. Even though it was my first full screen phone, I only used one of those screen protectors for a few days.
For 2 years it was always carried in my front pocket, mostly in my jeans or shorts, or whatever. I did drop the phone a few times, nothing really catastrophic, but the bigger crime I would commit with my phone is using it sometimes with wet hands, and once or twice I used it in the rain.
My screen for that phone is still in PRISTINE shape. Not a single scratch on it. It has a very very small ding on the phone from when I dropped it once, but when I went to switch carriers, the guy is like, "This phone looks brand spanking new."
It's true I used a silicone style case for the back of the phone, mostly because the N1 is freaking slippery....but the screen was immaculate.
A friend of mine has a similar story with his Iphone 3gs, or whatever it's called. The materials that the phones have been made from for the last few years is pretty durable. I remember watching youtube videos of N1's users taking their brand new phones and marring them with keys, pressing really hard, and they wouldn't scratch.
I have no idea if the screen on this model phone is made of anything similar in a material, but I would certainly assume so, I'm sure most if not all of full screen phones are just as durable.
I didn't even buy a back cover this time, and it's been great.
Anyways, consider going "naked" with your phone. It "feels better".