I think one of the reasons the 4-tip style Ansa/Monza mufflers don't sound as nice is because they don't mix the left and right banks where the tubing meets in the center, so they only exhaust two cylinders from each side. Does that make sense?
I had a Ansa/Monza that I was going to experiment on, modify the tubing to create simultaneous flow to both mufflers.
I think it would be a bit quieter than a Triad with the flat-pack mufflers
EDIT
I posted this in the wrong thread
... meant to post it in the " Mufflers, Holy crap! I haven't priced them in a while" thread