I agree with you about the rabbit hole that is espresso! It's a full time hobby on it's own. I need to share resources between coffee geekery and home theatre quite a bit.

I have a very similar machine to yours, mine is the Saeco Via Venezia. I secretly wish it would die so I can justify an upgrade, but is still pulls some pretty good shots. Does the Aroma have that pressurized portafilter? Mine did, I got rid of that right away for a standard portafilter which made a world of difference.

Those Mazzers are awesome grinders, but from my research they seemed to be a little more "espresso-centric" whereas the Rocky seemed to be more of an all around performer. I know for press pots I can grind coffee even coarser than it needs to be and get minimal sludge in the cup. I can also choke up my espresso machine at the fine settings. If you are looking for a great grinder, I highly recommend the Rocky. It has the same burrs and motor as the commercial Rancilio grinder and is built like a tank.