A lot of mods are pure snake oil in my opinion, you need to ignore what it says on the box and get to the real facts about them.
Why do people still believe that Induction kits add loads of power? This only applies if there is a restriction in the airbox and most standard airboxes flow very well indeed.
BIG ASS exhausts also stuff the exhaust flow rate.
I'd like to see people getting into real mods, rebore, cryo treating, balancing and blueprinting, porting, polishing and valve work, big turbos, uprated injectors and remaps. These are where the real power lies.
There are some great guides out there like this one and this one plus people should really search and read up the older threads on these forums and they will learn a lot, theres a hell of a lot of experience posted on SIDC.