If you want to stay away from the whiney "honda-vtec" sounding exhaust, I would stay away from a header.
I have the FSWerks Cold Air intake and the Race Exhaust. The sound on the highway is starting to get to me because our cars are typically at 3000 RPM... it gets a little annoying after a while. I love the sound around town and it does have a great baritone note at idle and with a quick blip of the throttle you can make the exhaust "burp" but not "crackle" like a Vtec engine.
If I were to order again, I would have gone with the FSWerks Stealth Exhaust.
Built Ford Tough... without your tax dollars.