[Blue]

The shorties provide little to no power improvements and I'm not sure what you get improved mileage. The long headers will provide increase power and increased mileage (as long as you don't jump on it all the time). I experienced a flat spot in my acceleration before the headers and after the headers were installed I will accelerate from idle to red without any noticable flat spot. If you primarly drive city streets the headers and exhaust won't make a difference. It takes a lot of fuel just to get the beast in motion. The highway driving is where you'll see the benifits. Make sure the pipes are legal for your state.