For some reason DesireZ seems to have absolutely awful touchscreen. It is not only imprecise, it is badly calibrated too, with no recalibration option. After 6 months I still can't get accustomed to it, as I use N900 daily and my brain doesn't get rewired to putting my finger slightly next to the items I want to choose on the screen.
Calibration is also more off on the right side of the screen than left.

Many of the numerous other out of the box problems can be circumvented, eg. you can add missing cursor keys by mapping dpad to unused keys (requires layout file editing as well as hex editing character binary file, so not a simplest of tasks), but not touchscreen calibration. If somebody knows how to do it, please tell.

I've tested couple of DesireZ models in stores at the time, and they did exhibit the same problem. Could be a bad batch as I didn't notice much wailing about the issue when the phone was released. Not all phone models with capacitive screens were as imprecise as DZ such as Samsung GS1. Too bad DZ was only Android model with hw keyboard available here.

Also one of my friends got rash in his hands from metal parts. The phone may have nickel in it's backplate or other parts, and there are people allergic to that.