I have a magnaflow single in dual out and then it is dumped behind the rear axle. I like that you cant see the exhaust but Im ready to run the pipes to the side of the truck because I don't like the drone.
On my XJ, I replaced my rattly cat with a little unit like this. After that I clamped on a fairly long cherry bomb of the Thrush variety. At the end of the bomb is a turndown. The exhaust doesn't even reach the back axle. My jeep drones, but it is a combination of the exhaust and the tires. I don't know/care what is louder, so I just crank the tunes. The main reason I run that setup is because I do wheel and everything is so compact up there. I'll probably never drag it on anything, so that is a win for me.
I had a flowmaster 80 series on my 2004 Grand Am GT. It was great untill I had the resonator cut out. Was only really loud if you stepped on it and stayed... otherwise it was just a little louder then stock.
My 2001 F250 I cut off the muffler, reduced the exhaust pipe size a little. About the same as my Grand Am. Louder then stock, but not annoying unless you floor it and hold it. On the interstate its killed by the road/wind noise.