I have reason to suspect many sp3 "user experiences" posted here. The pen is not laggy, and you dont have to press hard to write. The pressure sensitivity is comparable to the wacom sp1--though i slightly prefer the tracking and pressure curve in the sp3.
It makes shading in drawings really easy to do. I made my first drawing on my SP3 the day after buying it. The problem is, I don't think there is much demand for stick figure art.