If I were to go with a single, I would just get the one that's a good deal. The sound difference in single mufflers coming out of a stock manifold is minimal. If you want music, you gotta go duals.

1962 Fleetside 4spd 235 w/O.D. posi 3:90
In the Stovebolt Gallery
1990 Subaru Legacy Wagon AWD 2.2 5sp
2013 Ram Tradesman C/V
My Webshot Photos]