I heard a rumor that the timing curve on the A9P is a little more aggressive, but have no specific information to prove that.
I do know that the dashpot setting on the A9P is a little irritating. I've got a stick (NV4500) and have the VSS hooked up. The dashpot setting keeps the engine RPMs up at ~ 900-1000 as I coast to a stop. Then the RPMs drop to 650. Makes it difficult to get a smooth start if, say, the light changes as I'm coasting to a stop and want to keep moving. I've gotten used to it, but really wouldn't mind if it didn't happen...