Hey Guys just wondering what do you think, im not gonna hate Positive or Negative Suggestions and Opinions will be appreciated, specially the "Negative" ones to make an adjustment and make it perform,sound and look better,

P.S my Car is Automatic and i already know that some of you will tell me dont waste my money getting this and that parts bcoz its Automatic my only reason on getting this parts is bcoz i just want a good looking car with a nice sound and lil bit gain on the power not a whole lot just a Lil bit and a lil bit gain on the gas mileage if im not mistaken getting the parts will get me more gas mileage NeWb here.

Heres the parts im thinking

*Greddy Ti-C Cat-Back Exhaust System
*Skunk2 Mega Cat-Back Exhaust System
*GReddy EVO2 Cat-Back Exhaust System
*DC Sports Stainless Steel Exhaust Systems
*MagnaFlow Cat-Back Exhaust System
*A'PEXi N1 Cat-Back Exhaust System
their in order to my liking

*DC Sports Ceramic Coated Header 4-1 Piece
*Megan Header
*DC Sports Race Header

on the header does it matter if its automatic or Stick?

thanks