Magnaflow sounds alright it did on my V6 but they sound all the same. I would say that the magnaflow on your car will sound like the stock muffler on the new Civic Si's, they sound magnaflowish. My bro has a Flowmaster 60 on his 94 Mirage and its sounds pretty good and doesn't get louder as you floor it.
Magnaflow has better build quality for sure, theres no doubt about it but each of them have their advantages. For one the Flowmasters don't stand out since they are black.
Let us know what you end up doing and post some video clips with some great audio behind the mufflers whenyour revving and when your driving by