First of all, it's never okay to slowroll. Ever. Slowrolling is a total dick move and one of the cardinal rules in poker etiquette. Do this live at the wrong table and you're likely to leave the casino minus some teeth.
That said, I don't think you understand what slowroll means. Since you state your intention is pretty much the same as a slowroller (i.e. to be a major dick) then it's probably moot, but technically a slowroll can only happen when you're closing the action with the absolute nuts, e.g. you're last to act on the river or facing a shove, and your hand can't possibly be beaten.
In any other scenario, you can't technically slowroll, including preflop with AA. There are actually certain tournament scenarios where tanking or even folding AA preflop is advisable. In a cash game or a routine tournament scenario, some may consider tanking with AA preflop a form of slowrolling, especially if done only to tilt your opponent. However AA can always be beaten so it's not technically slowrolling.
Slowplaying is not slowrolling. The former is an acceptable and often strategic play, while the latter is never justified.
Regardless, intent is the important factor, and your expressed intent seem to be to the same as a slowroller, so I would strongly advise you to stop it.
