I have not seen any documented Hp/torque increases posted for the Borla system. Anybody else feel free to correct me on this.

I have heard the Borla system. It's nice but really pretty mellow. Very little louder than stock. It does have a nicer low speed/idle tone than the stock system but adds a right angle resonator behind the driver's seat area and is probably only a little less restrictive. If you shop around you can find the Borla for between $600 - $700 dollars.

I have the new Magnaflow system. It can be had for about $550 dollars delivered. It is a straight-through twin side-by-side muffler design and sounds pretty rude compared to the stock set-up. I never made any stock base-line quarter mile runs so once I get to the track it will be in modified condition so I don't have any scientific proof of power gains. I did pick-up about 1.5 mpg since installing the Magnaflow system. I can't be sure if that is because I'm hearing the motor better and shifting at a lower point or if the lower backpressure/improved scavenging is helping efficiency. Either way, I'll take the improvement!

Slim