I don't know the dogcam, I use a Go pro (great for daytime footage crap for night) and occasionally I dig out my old Veho Muvi..very cheap, very small and very disposable for more risky ventures (wont loose sleep if I lost or damaged it). But not waterproof in any way.
As for the choice to film. I've used my cams essentially as a black box recorder and delete almost all my footage without even reviewing it. If something interesting happens, or I film mates then i may publish the footage but i generally never use it to out bad driving (i think I may have one example on my channel...
http://www.youtube.com/user/jonnygeez?feature=mhee...) I do also use it to film good driving experiences and have sent footage of drivers that who have (in my opinion) driver very well, to their employers to thank them.(that always confuses the viewers and their comments).
That said, for the last few months I've not mounted the cam and haven't really missed it, perhaps the summer will invite more attractive footage.