[phlabrasca]

The K&N does not add 28hp.

The Borla exhaust will not rattle when hot unless it's touching something. I think you read my complaint, and basically the problem was that the IS-F does not have much clearance for pipes, so the Borla is a very tight squeeze. This was resolved with a few trips back to the installers. They eventually had to spot weld it in place.

I like the Borla catback exhaust. I removed the K&N intake because it did nothing and just made it ridiculously loud when the car was open throttle. The K&N sounded better when I first installed it, then as the computer got used to it, the growling it made over 3k rpm started to fade away, and the only sound left was a RIDICULOUS growl at 4k+ rpm.

 

[phlabrasca]

Umm just a note. Eisenhaus has no relation to Eisenmann. I hate to spread rumors about stuff I don't know, but I did read a long forum thread somewhere about how Eisenhaus basically copied Eisenmann except they source cheap parts from Korea that do not come close to mirroring the quality of a true Eisenmann exhaust.

I have the Borla Catback and it's beastly, very very loud.