From what I can recall, I didn't like the sound of the Magnaflow. It was too loud (for a Saab) and had a bit of a hollow sound, maybe the result of the turbo. If I were the original poster, I'd stash the $200 or so that it'd cost for a new muffler/exhaust into a PPC fund. A stage 1 will be fine without a new exhaust. If you go for a more complete performance tuning scheme, than a high-flow exhaust is necessary, not for the sound but for the performance increase.
Although it's comparing apples to oranges, I remember when I worked as a service writer for a Harley-Davidson dealership. Stock Harleys are actually pretty quiet bikes, but they sound kinda lame. So everyone wants a new exhaust, or at least some slip-ons. And people would cheap out and not go for an EFI remap or jet kit and the bike would run *horribly*. Or they'd be all tough and get straight pipes which also run poorly except at WOT.
The Saab has enough noise intruding into the cabin because of the stock tires. I think adding a louder exhaust would make it worse and most aftermarket exhausts are louder, unfortunately.