It's all up to you and what you're willing to live with. If you want to push that much power you'll have to deal with the noise and vibration from having a race header and free flowing exhaust.
My plan is to get a Steeda short-ram intake and have Tom do a custom tune for me and call it a day. It'll be good for extra power but it'll be much easier to live with than going all-out.
2011 SES 5spd #006 >> SR #213
Join the cause! 3 Door Fords for America! facebook.com/3DRS4US
What other people think of me is none of my business.