My suspicions have recently been confirmed!
Big JIm

Hey, at least he's enjoying the Kool-Aid... Let's call it "stimulating the economy"... Buying those things is putting money into our economy, lol... Even if they don't work he's keeping someone in a job...
The facts are though
1.) K&N on a stock truck - nada
2.) Throttle Body Spacer - even less nada
3.) Tuner - more nada than either of the two above, but not worth the money
4.) "Forsed" air intake???? I have no clue what you mean by this but if you are talking about forced induction (ie turbo/supercharger) that WILL work, not for $200 though... Hell, if you can get a turbo for $200 share the love, let me in man!
5.) High flow cat? Have you actually seen the inside of a catalytic converter? Obviously not, because if you had you would know there is nothing inside to cause any obstruction that would warrant a "high-flow" version, much less on a stock truck...
6.) A different muffler will definitely get you a different sound, more power? Ok, I admit, you *MIGHT* see 1-2 hp increase but, honestly the only reason you should get a different exhaust is if you wanted a different sound...
7.) How the hell would a tuner give you more air?!?! More fuel, sure but, what good is that with no more air? It's not... A tuner can advance timing curves and increase high rpm power... Not worth the money though...
8.) New plugs and wires? Ok, this is even more absurd than the other crap... If you NEED new plugs and wires, sure they can help but, just changing plugs or buying those expensive things won't do diddly...
Basically all these companies are doing is trying to get you to waste money on crap that makes you THINK it would work... It's a truck, not a racecar... If you need more power I told you how to make it... None of this other crap will work... Just trying to save you money...