I can say with certainty that two of the three X's received have had problems unrelated to "user error".
First one had issues with: touch screen responsiveness, call quality, battery consumption, and a 'dead pixel' after update.
The second one froze multiple times and had a screen with reddish contrast/ decreased sharpness.
Thus far the third one has been problem free.
All three have had the same apps installed and run under similar conditions.
Verizon telephone support has been great through all this and has sent a new replacement each time. They even extended my worry free warranty another 30 days so I won't be stuck if a problem arises.
The two X's issues were manufacturing and software related.
No user error involved.
My phone from time to time will become unresponseive.. a simple reboot, deleting of all cache, and time normally fix that, Along with a auto task killer. Now given i am rooted, running Auto task killer on strict settings, and with my cpu underclocked when the screen is off to 300mhz, when my battery is <40%, and differently under certain conditions.. With any technology freezing can be an issue...
Your battery is ALWAYS going to be like that on a new device. The NiCa(i think?) batteries in these phones need to be broken in; and it will not have be untill multiple complete power cycles are gone through. That means battery charged to 100% and then completly diminished. That is how you keep your battery life too, rather than short spouts of charging then using the battery for a short period of time.
If you are worried about bettery usage look at your apps. The facebook APP will use Far more battery than most other apps because it is constantly running; Along with others similar(myspace, other social networking).
I have never heard of an Update causing dead pixels. So i find this highly unlikely, and in a phone with the resolution the X does in a screen size this size you probably won't immediatly notice the dead pixels unless your screen is white. A stuck pixel is more likely as it would be more noticable, however those are fixable(to an extent) by many apps on the market which flash different colors on the screen.
Your second phone with the screen may have been a manufacturing issue, but the freezing probably could have been fixed with a simple reboot/Hard reset.
What the general public doesn't understand is that software this complex is going to have it's share of issues. Nomatter how refined the code is it will always have it's "qwirks". But When you do not have the general knowledge to trouble shoot an error/issue you will claim the piece of hardware or software is defective.
Like sund0wn stated, only about 5% of the phones actually have any real issues.
Working in the IT field and working on servers, if you thought a server was defective because it didn't run correctly then you would never have a working machine. Backing up data that will fail one day but succeed for a month after that then out of no where fail again where all settings are the same and nothing has changed.
Now i'm just rambling, but you get the point. lol