I've been using an older tablet PC for notetaking for a few months, switching from a combination of typed and pencil + paper notes. Anecdotally I think think is the best notetaking solution I've yet tried since:
* No smudging (left-handedness issues solved!)
* Never out of paper or space to write
* Very fast erase, almost no cost to correcting mistakes
* Can move things around on the "paper" very quickly
* Copy and paste, resizing, shape recognition, ...
* Can insert graphics, formulas, etc as needed, quickly
Honestly the only downside is battery life and I'm working around that with a 2nd battery. My overall note quality has massively increased and I find I can keep up with lectures without any trouble, something I often couldn't do with only pencil + paper due to my slow writing speed and frequency of mistakes.
Specifically I use xournalpp [1] and ipython with a custom onscreen keyboard layout for math-related activities. It works exceedingly well for a ~$300 total investment (used PC + FOSS apps).
I concur; xournal with any old Thinkpad Tablet PC is definitely the sweet spot for me, too, and it has allowed me to go completely paperless for a couple of years now.
My experience of taking notes that way on the Surface Pro 2 wasn't fantastic. It feels different to a pen and paper and that's probably my biggest issue
The screen is a little too narrow to be comfortable in a portrait fashion and too heavy to hold in landscape. The pen also has some calibration issues which makes my handwriting much larger and less legible than it would be on a notepad.
The SP3 should fix those issues, I think.
It's a little better for mind mapping since I'm able to move the page around, erase stuff and use colours, but I have to hold it in landscape. I think the larger screen of the SP3 would help there too though.
