Having raced oval myself for about a year I can say it's a completely different form of racing... with off-road your "pucker factor" only kicks in when trying to make a pass, and with oval you're constantly trying to make a pass and it's all about getting through traffic and trying to avoid the...
It's been a few years since I ran oval, but my personal favorite class was 4WD Late Model:
https://www.rcgroups.com/forums/showthread.php?3253853-REVIEW-PR-Racing-SB401-LW&perpage=100#post41360325