Exactly what I did in 1977.I took the Campy brakes off my Bottechia pro(which actually came with universal brakes),and put them on my Mercian frame.Then I installed Campy SR crankset,SR pedals,SR Titanium spindled BB. Like Otis said, we would mix and match.I was a weight "nut"(can't bring myself to call myself a weenie),so I used a Suntour GT real derailleur(the Superbee-sic-stuff was a bit heavier than the GT),front derailleur,and shifters,and I used HiE hubs.
Everyone mixed and matched.Campagnola probably was the prettiest, but it cost 4x what the Suntour parts cost,and SunTour was a bit lighter(usually-not on the BB or SR Crankset,or the HiE stuff).Yeah,the Campy stuff did work the best,and it sure as heck held its value better(sold it for 3x what I paid for it in the late 70's)
Corvette guys,and other hot rodders from the period(actually the period was late 60's for cars) did the same thing.They never stayed with the stock carb-EVEN WHEN IT WAS ACTUALLY BETTER.I put a dual feed dual pumper 650 Holley on my 1971 383 Cuda-even though the stock Holley with vacuum secondaries worked better.
Hot rodders, bike racers,and bike weight weenies always changed stuff-it was part of the period(still is).
Thanks,
Charlie