Pressure sensitivity comments have focused on the fewer increments of pressure for N-trig compared to Wacom. This is a false issue. The real issue is the pressure sensitivity curve, which is definitely less optimal in my hands with the N-trig pen. For me, this is not a big deal, but it may matter to others. There is a tool coming soon, according to press reports, which will adjust this curve.
There is also a phenomenon where pressure sensitivity disappears if you adjust the screen resolution. It is not absolute and seems to be dependent on the use of wintab drivers.
Toon Boom products allow you to turn off the wintab drivers in the preferences section of the programs. On a new Surface Pro 3, this was a very unsatisfactory experience. However, recent updates to the machine from Microsoft have turned this into a better experience. This was the surprise of my recent retesting. Some tools seem to work very well without wintab, while others develop strange artifacts. For instance, pencils seem to behave very well, while pens develop an unacceptable jitter.