I would say that aerobatics has the potential to be a dangerous thing however if you find yourself a good instructor then aero's can only make you safer in my opinion.
Having experience of operating your aircraft in all areas of the envelope including unusual attitudes and the like will improve your handling skills no end. You also tend to loose the fear that some PPL's have of stalls/spins. Not to say that you become ignorant to the dangers but that you become more aware and less scared.
You also begin to truly think and control the aircraft in all three dimensions. Once you have rolled, looped and spun you and your airframe through the skies you will wonder why you didn't do it sooner!
I don't have any experience of the AOPA Aero's course but I hear it is quite good.
ASI