I agree Lancaster. Props if it happens, puking smileys if it doesn't.
Also, 9 times out of 10, I would rather pay a mechanic to do the work. Sure, I've changed the IAT sensor, TPS, MAF, Plugs, wires... y'know, simple things. I would rather pay a pro who has the tools, know how, dedication, and time to "soop up" my ride. And anothe rnice thing about paying a pro, if they mess it up, they fix it at their cost, I mess it up.. I'm SOL. Also, some high performance parts like superchargers, tubros, etc have warranties and are VOID if not installed by a profesional and you obtain a receipt for the install.
When it comes down to it... I haven't a clue when I would have the available time to have my car out of commision for weeks while I work on it... minutes are all I have in a day anymore.