Ok the Injen CAI was installed by me about 2 months ago. I can report that id does definitely give the extra power claimed... but your gas mileage around town may drop by 3 -r 4 mpg. due to the urge to use that power.
The instructions are straightforward and easy to follow. To keep heat from the aluminum intake tube I wrapped all but the MAF sensor area with exhaust heat tape and sprayed it with aluminum high heat header paint.
This CAI was designed and manufactured in Japan expressly for this engine. No "check engine" lights will come on and Toyota dealers are OK with it for the guarantee, as are Las Vegas smog check stations. It's NOT legal in CA for lack of ability to capture minute emissions coming backwards thru the intake occurring after engine shutdown. Picky, picky!
