Yep I used to have a nexus one at some point and it felt a lot more "fall resistant" than the iPhone indeed... I also don't care too much about plastic VS glass. Actually I like technology stuff made of good plastic cases, like 80's home computers ;)
I've personally seen MANY shattered SGS2's and already 1 shattered SGS3.
If you buy a glass front Android device because it's "more durable", you're going to have a bad time. They use the same or similar glass suppliers, and it will break very easily.
I agree. The Kevlar back on my Droid 4 feels like it's more shock resistant than a glass or aluminum back would be. I also like that it's water resistant.
I personally don't mind plastic if it's done well (eg. SGS2/3), but metal and glass does feel nice in the hand.