Cell phone carriers are like cable carriers now. Everyone has a good and/or bad story about them, and they'll do everything to get your business but not much to retain it.
Consequently, I've dropped my dX several times and it's still going strong.
You hit the nail on the head when you said that they’ll do everything to get your business but not much to retain it. That’s how Sprint got me - they offered the best Android phone (at the time) and AT&T was late to the game.
AT&T had become iPhone-centric, and all their other offerings were low to medium end phones. Combined with the service quality, it wasn’t hard to leave at all.
Now that there’s so much competition, it’s gotten very interesting, and very rewarding for the end user.
By the way, I’ve heard great things about the Droid X, including it’s toughness. I have dropped my EVO once, but it was okay.
I could never go smaller than a 4.3” screen now. I love FReeping from my phone!