2k8 was not a dunk fest with proper D and playing against ppl who don't exploit. I will say that the post play is more physical now, but I'll take two sim players and a more realistic mid/3point game over what 2k12 has to offer.
With 2 sim players going at it, 2k12 no longer holds the adv, because the only downside that 2k8 has is nullified by sim play.
With that said, it's still not exactly a big challenge to attack the basket in 2k12.
Don't forget the cross court passes on a dime. I remember playing around one time and had my roommate cherry pick when I got the rebound. Shaq threw 4 cross court alley-oop passes in a row right on the money. The passing in 2K8 was just awful. Forgot to add that before.