I have always fed my Oscars on Hikari and Tetra pellets, I believe these to be some of the best on the market and all of my fish love these, not only the Oscars.
I think you are feeding your fish perfectly okay. People often are how many pellets should I feed my Oscar?the easiest and best way to feed your fish is not by how much food, but actually for how long. Feed your fish for between two and three minutes and they will get more than enough food.
I thought I would also add that I also feed my fish on the kril, , shrimps, frozen lance fish, cockles & muscles, the Oscars absolutely love all of these food