I've been really pleased with this one:
G1W-CB 1080P HD Car Dash Camera /w Capacitor
It's a "generic" camera but this vendor stands behind them. Has all the basic functions without a lot of frills. I'd highly recommend getting one of the capacitor-powered units (like this) instead of one with internal lithium batteries... batteries don't stand up well in a high temperature environment (like stuck to the windshield of a greenhouse... I mean vehicle).
The HD video from this thing is pretty awesome.
2016 Coachmen Pursuit 31BD
2015 Jeep Wrangler Sport Toad
Nights camped in 2016: 19