Are you talking about an action cam (like what GoPro does) or a dash cam (for recording traffic, documenting incidents and shit) ?

Dash cams differ from action cams in that a dash cam is built to turn on and start recording automatically when powered up (so it just sits there as part of the car and you don't have to do yet another THING every time you get in and start driving) while action cams are made to be portable, have a battery and require user interaction to start filming.

For dash cams my opinion is the A118C is killing it... I have one in my Jeep and one in my wife's car, and about to buy a 3rd for my daily driver. http://www.amazon.com/gp/product/B00SK8B47W/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1

For action cams, Drift Ghost is comparable with GoPro on basic specifications but WAY WAY WAY better on user interface and useability.

(I personally can't stand GoPro, bought and returned a Hero3+ when those came out and so glad I didn't keep the stupid piece of shit - I have no idea why they're so popular)

For another action cam option, and the one I ultimately went for - the Kodak SP1 - is pretty awesome; it has some significant advantages over GoPro like not needing a case, not needing a separate screen, easier file/card access and since its lens is interchangeable the "dry" video looks better and the underwater video looks better (less frame distortion) .

Here is dash cam video from my A118C - make sure to select HD from your youtube player if it defaults to the 480p player.

Here is windshield-mounted video from my Kodak SP1 - again make sure to select HD on the youtube player.