I don't have drilled/Slotted rotors on my 78 but do run Performance Friction carbon Metallic pads which are terrific-quiet, tremendous stopping power, rotor friendly, and little dust. Not a fan at all of ceramic pads which are designed primarily for daily drivers that want a quiet (I have never had an issue on any car with noise from brake pads so not so sure about the quiet issue with ceramics) and low dust. The hidden secret is that ceramics will not brake as well as semi metallics, carbon metalllics, or ferro carbon pads.
I do have drilled/slotted rotors on a 1994 Mustang GT and a 2001 Pontiac Grand Prix and these rotors definitely improve performance. Don't believe the nay sayers who say that there is no advantage to these types of rotors on the street-NOT TRUE! Under hard braking there is a definite braking improvement especially as the heat builds up. The rotors run cooler and stay cooler longer! The biggest advantage on the street for drilled/slotted rotors is wet weather braking-unquestionably there is a tremendous improvement on my cars!
Hope that helps!