I have the Borla Dual axle back. There is no muffler on these. That's mostly why it sounds different. You have to remove the muffler at the end of the stock exhaust system and replace it with the straight pipe.
I love the sound of mine. Around town as the revs are always moving up and down it sounds great. The only time it bothers me is when I'm on the highway and the engine is turning around 3000 rpm. At a steady speed there's no problem, but let off the gas and there's a bit of a drone as it gradually slows down. Depending on the traffic flow it can get annoying - especially with passengers and I have the music turned down lol. I'm hope to put some sound deadener in the cargo area this summer and I think that will take care of it though.