I worked with mine quite a bit the first year I got it. I tried several different powders, and pellets. BlackHorn 209 is the cleanest powder by far. I picked up some Black MZ that I have not tried to date.
Using Harvester Sabots, and 45 cal 250 grain Hornady bullets. The Optima is capable of 454 performance if you can enjoy that much recoil. Mine shoots very impressively. No problem with accuracy or power with the Optima.

Bob R