4.2.2 should be out relatively soon. I have a Nexus 7 and haven't experienced the lag associated with 4.2.1, but if I may make a suggestion: Do a factory reset. Apparently that's solved the lag issues for most of the people having them. Give it a whirl and I'm 99% sure that it'll solve your lag problems.

For in car you'd go with the Nexus 7 (which is a Google device made by ASUS).

http://forum.xda-developers.com/showthread.php?t=2019532

I had a Nexus S 4G (which sadly died a month ago), I rooted it from day one and ran custom ROMs on it. Mostly of the CM variety. Reason for doing so? Additional features that CM adds. All of which are mentioned above in the article.

I don't know what made my morning more. The fact that when I woke up at 6AM and turned on my TV the Science Channel was airing a Firefly marathon (of all the episodes) or this video.

I started reading and got significantly along in this article and I had the following thought, "Man, this seriously sounds like something Rob Bricken would write. Alcohol at the end of times." I scroll back up looking for the author and nod smugly to myself while saying, "HA! I knew it!"