Thanks for confirming that it's not just a dud device.
It's the inconsistency that is puzzling. Sometimes it works when I tap right on the spot, and sometimes (the majority of the times in my tests so far) I have to tap off to the side. (Which makes it seems more likely to be software rather than just calibration.) And in some cases it's has if it doesn't know it has been tapped at all. The total-ignore thing only seems to happen when trying to tap on controls, not with page turns (so far anyway). I haven't tried much in the way of selecting words yet to see how that goes.
Oh, and it is
exactly as bad as I am seeing, it's a bit hard for it to be anything else.
However, I will admit that the problem probably won't be all that annoying once I get beyond playing with my new toy and get down to actually reading.