Buying a 29 ft keystone Laredo for the family vacations. As we all know the 5.4 isn't a HP monster so I'm planning my upgrades. I'm doing an intake, SCT programmer and a cat back exhaust. For the intake Im going with the AIRAID system. I did my homework on tuning and 5 star seems to be the guy getting all the kudos on the 5.4. I haven't decided on an exhaust system yet. What upgrades has everyone tried? Positive and negatives?