I just got an 05 Outback XT I wanted to swap out the Exhaust and add Headers in. I also live in MT where there are no emission standards. Some of my friends have said to remove the cataltyic converter and resonator but I am also very new to subie mods so I am not sure if any of this makes sense. I heard this (
That exhaust won't fit on his car anyways. That's a WRX in the video. TurboXS does not a make a Legacy/Outback muffler. Be aware that you may want to avoid loud exhausts considering the sound will resonate inside your interior.
A header is a waste of money at this point. And you will need to get tuned if you do full exhaust.