Surface Book is brilliant. Solid as a rock, keyboard better than a Mac. Battery life in tablet mode sucks, but as a laptop it's excellent.
That said, ever since the Intel firmware fixes addressing the power management issues, the Surface Book has been the perfect general purpose mobile computer for me. Crisp screen, solid keyboard, long battery life, lightweight, and the stylus has been sufficient for replacing good ol' pen and paper when I need to scratch out some math for my occasional graphics programming hobby work. (I have a dedicated GPU model.)
It's the first new computer I've bought in 4 years, so despite paying over $2000 for it, I'm quite happy with the value I've gotten.
DPI oddness (moving between low DPI external monitor and high DPI internal one triggered it) seems much less now.