I am sure the old So-Cal still works though, it can be found on the forums or mods section of the BeamNG site if you don't wish to donate to the project. So-Cal Interstate is deprecated, the new version is Los Injurus City map project, which is currently available to those who donate to the project via Patreon. Traffic works well here as it always did. It's enjoyable if you want an invigorating twisty road full of nothing but hairpins, trees, and occasional embankments to fall down. Tail of The Dragon is a rather 'small' (by mileage standards) map I made with just the 12+ mile course in Deal's Gap on the Tennessee / North Carolina border. The AI has not been updated to include 'one way roads' yet because the map is old (that's coming next month), but the AI will work in a basic manner, and it does have 60+ miles of roads. Nevada Interstate isn't an overwhelmingly huge map like Desert Highway or Roane County, but it is fairly large and has a 13.x mile loop of interstate highway that doesn't know it's not a race track. The AI on Roane County should be pretty flawless as it was just updated with improved AI for the Traffic Tool, updated bridges, and new highway textures that I custom made. Roane County was actually supposed to be only a concept, a test bed for large open worlds but it worked. Roane County is just a few % bigger than Desert Highway, but has much more roads and buildings (though Desert Highway has been around since before Roane County, too).

Roane County TN USA, in it, the road that goes through Rockwood and Harriman downtown goes for over 18 miles from north to south end of the map.

Beamng drive highway map