I picked up a SP3 i5, 128gb two days ago and I've been experiencing the jittery line problem that has been reported here since last October.
I'm a professional graphic designer, focused in illustration and hand lettering. I bought a SP3 because I read reviews from trusted artists (namely Frenden. You can read his review/comparison here.)
that said this device was stellar. However, this jittering is a colossal failure. The thing I need first and foremost in a tablet is accuracy to my line work, whether for inking illustrations or lettering. I found the image a few pages back defending the Pen's
accuracy gross and inapplicable as it shows a robot holding the Pen at a 90 degree angle to the screen when the vast majority of people hold a Pen at a far lower angle. Secondly, I have a steady hand but I'm only human and that's what this device was made
for--not robots. So showing a robot arm making perfect, unshaken passes is laughably irrelevant. Lastly, what's also not known about that image is the speed in which the robot arm makes passes over the screen. The faster you sketch, the less this problem is
evident. But human artists need to make small, meticulous details that require slow careful passes with the Pen.
Here's an example of me doing some basic lines and lettering in Photoshop CS6. I used the utmost basic settings for my brush (no brush presets, shape dynamics, scattering, etc. turned on. Just
a basic circle brush with 100% hardness). I made certain my N-Trig drivers are up to date and my pen's batteries are full. I tried sketching "SEND" and the result looks like I was going for a worn, Lord of the Rings-style of roman serif (I wasn't).
People are absolutely not blowing this issue out of proportion or are the victim of isolated faulty hardware. It's undeniably clear that this is a problem that affects all SP3s and I find Microsoft
and N-Trig's seemingly deliberate inaction disappointing and unprofessional. This problem affects me far too directly as a designer to enjoy the SP3 as an otherwise excellent device and so unfortunately I'll be returning it.