Here's some random experiences I've had with the Eternity after nine months. This site has made the phone more fun and usable. Thanks to everyone that contributes.
1) After a master reset I lost the file structure and the phone would power off and on if I chose the background feature or pressed the purple folder in My Stuff. AT&T sent a refurb yesterday, no problems.
2) The keypad appears smaller in-call than the normal dialer and it's difficult for my fingers to dial account numbers, etc.
3) The bottom right corner of the screen where the menu button is located had to be pushed fairly hard for it to respond. The rest of the screen had grown less responsive, but still usable with harder taps. That may be my fault for pressing too hard over time.
4) The screen doesn't scratch easily, but if you rake the tip of your nails across the screen scrolling you'll cause faint lines.
5) The battery seems as powerful as the day I got it (power down each nite).
6) The cramped keyboard is my biggest complaint. I solved this with a Nintendo DSi squiggly stylus I got at Walmart (7.99). The stylus easily hooks to my leather case.
7) The phone is lightweight enough to forget it's in your pocket. The 3.2in screen is great for browsing using Opera Mini. The calender is easy to access with the middle hard key.

The radiation emitted is among the lowest among cell phones.
The Eternity's a good phone. The Impression would be a good choice for the keyboard and screen, but the shorter battery life and larger form would be a compromise. Besides the Impression ain't purty to me and feels plasticky with loose buttons.
I think the screen sensitivity will be the first thing to go. I predict two years max but maybe with soft stylus use it will last longer.
The main reason I went with AT&T and the Eternity is the $15 unlimited data plan and the ability to tether if I'm in a jam. I didn't need smartphone features but the internet (information) is important to me. I think data plan costs are going to increase and feature phones are going to be treated as smartphones. Hopefully I'll be grandfathered in with my current plan for a while.