On the expensive front, the ultimate thing seems to be
ChaseCam. If you buy all the right options from them, you can have 1-4 cameras, accurate GPS + G-force, OBD-II, as well various other external sensors (independent RPM pickup, and a whole lot more), and it all logs in sync to a memory card. The problem is price. I just can't justify the 2-3K+ even for a basic setup that does a better job than my hackish Android stuff (which works "good enough" for amateur-level playing around anyways).
e.g. check out this sample video, where it's even logging all kinds of suspension/wheel-based data: