magnum heads

i just got a 360 out of a 99 ram 2500 (freebie) it runs but has a slight knock. i was wondering if the heads on it are better than the heads on my 360 in my duster. my engine is a 77 360 out of a van with stick heads, ported, new valves and stiffer springs. i had heard that the newer heads flow alot better. should i build the magnum heads and out them on my duster? what are the benefits?

thanks