Don't know if I've ever heard glasspacks on an Oldsmobile, they sound pretty fantastic. They have a lot of the deepness I love with the Super 44s, might actually sound better than them. Hard to tell when they're not side by side.
It's also funny the way different cars react to various exhaust systems. The system on the Cutlass dumps before the axle, and even though it's Flowmaster, there's no droning, but it's a little quiet. I have a '70 DeVille with Flowmaster 50s -- the quieter ones -- and a complete system, and it droned terribly. Both cars have about the same CR and factory heads, the DeVille has the factory cam, a crossover, and lots of insulation, the Cutlass has a bigger cam, no crossover, and much less insulation, and yet the DeVille is the one that had the drone. It finally went away after about 1,000 miles.