deckplate+catback.. worth it?

Want to give my truck a little more umph, but don't want to sacrifice the great mpgs either. I've been seeing mixed opinions on the deck plate as well as catbacks.. Are they worth it, or should I put my money elsewhere and not even bother with these two mods..

 

Deckplate is cheap so I say why not? As for a catback, I'm not sure. They seem pretty pricey. I think of a cat back on a N/A V6 as more of for sounds. And if I wanted to change the sound of an N/A motor, I'd just cut out the stock muffler and replace it with something of your preference. If you were supercharged, thats another story.