I dont use either Norton or anything microsoft based for my security. I use something a little different. Through various tests, I have shown my choice to outperform almost any other AV suite on the public market. I'm happy with it and I'm not going to force it on anybody else.
As far as car hacking goes, I really dont approve of all the various ways a dedicated hacker can gain access to the on-board computers in my vehicle. Although the Cruze isnt as bad as some. I will never own a vehicle with wifi access though. I would rather install my own car-puter and secure it as I see fit instead of trusting some unknown in a cubicle somewhere. That, and my car-puter isnt tied in to any of the on-board systems other than audio out. Popular mechanics did an article on this very thing a few issues back. Very informative.