Nobody is perfect. For me it's the best Tablet PC I have ever owned but I have been using TabletPCs for longtime. Long enough to be using the pen as my main input method.
Yes, the documentation is generic and the tool already existed before but could not be used in the SP3. My guess is that they changed to make it compatible with the SP3.
Well, keep in mind that MS may decide that the current setup and driver give results that are within their QA parameters. So, it's hard to say. I'm planning to install this Samsung patch this evening.
Here is the thing. I have seen many pictures like those and never stopped to check if mine is curved or not. To do it I have to remove mine from the case. And that's enough for me let it be. As far as I can see, mine is totally functional and that's what matters to me.