Is buying full exhaust worth the money compared to the cheaper slip on muffler?

I have a suzuki 400 Quadsport and want to improve hp. Should I spend the extra money, or is the slip on muffler just about as good?

Is buying full exhaust worth the money compared to the cheaper slip on muffler?
Save your money. The replacement mufflers are just as efficient. Don't think it wiil imrove horsepower though.