My .02 on this -
1. you can substitute a straight pipe (stinger) for the last section if you desire a more agressive tone without loss of performance.
2. motors need some sort of back pressure to run most efficiently.
3. I've "read" that Alfa knew what they were doing with regard to the 3 "cans" of the stock system.
4. The first can is more of an expansion chamber than a muffler.
I like to run all 3 cause I'd rather hear the motor sound than exhaust sound.
The Magnaflow sold on the BB runs the middle and end "can" and a lot of people like it.
Loud pipes save lives.
1973 GTV - bought 3/06, intend to keep forever
1969 GTV, #AR1530021 - sold 10/72, guess didn't intend to keep forever
Current project: '69 Corvette bought in '73, DD '73 - '80, in storage 1989-2002, now apart