So the 2004-2009 4Runner one is definitely not the right one. But I bought mine at sprintboosterusa.com and they will send me the one that should fit. Once I get the right booster unit I will update you guys.
I've always wanted to install this item in my 4Runner, but never really made any real effort until recently by taking photos of the plug and trying to match it.
My first experience of the Sprint Booster was in my Mark X in China. It really wakes up the car and remaps the throttle curve. Toyota really programmed the throttle curve too conservatively. Even if you don't run it in race mode, the sport mode makes the car alot more responsive.
I don't think it's snake oil. One reason why I am trying to get the right one for my 4Runner.