I did try it a bit late last night, and it was as expected--they were rock solid, and it was actually a bit weird.
When running in a plate race on iRacing, I'm used to cars bouncing all over the place, so it was very odd running in a perfect draft train, without any crazy stuff happening!
I changed lanes and maneuvered through traffic without any issues. When they release the full AI suite for oval racing, I still firmly believe I won't need to boot up NR2003 anymore (or Heat 4 or anything else) for my racing fix.