I haven't dealt much with C-band. The center versus offset method will definitely affect aiming and if you need offset (like D* and E* normally uses) you'll need a different arm. Will you be using the motor for positioning? Also with C-band I'm thinking of those big 3 meter solid or mesh antennas. I know it can be done there's a Bar in my neighborhood that put a digital lnb on their old c-band dish.