When flying a massive craft with not-overwhelming amount of SAS strength, like 1st stage with non-gimbaling engines, it takes too long for ASAS to kick in with sufficient force to keep the craft veering off target. From what i've gathered ASAS will use force in proportion to how much the course deviates from the desired one but when that little force is so low, that it cannot overcome the force causing the spin, it can easily turn 10 degrees before ASAS finally starts using enough force to bring it back. When this happens in the middle of a burn to orbit it causes the final orbit to be several degrees off. If i wish to achieve nice equatorial orbit i have to manually adjust to the deviations ASAS "ignores". It's not all bad, of course i have noticed the great improvement in aircraft control and conserving RCS but in my opinion the ability to trust ASAS to keep the direction it was told to was worth these slight drawbacks, as that is it's primary role.