Those performance chips are a big question mark. Kinda like do UFO's exist? Does Big Foot really live? Do performance chips really work?
Some people will swear by them, some will say they're crap and waste of money. Some of those "chips" such as are available on ebay are just some kind of resistor or diode, that really doesn't do much. But they are pretty cheap to try. Might not hurt.
I have a beatup 1991 Geo Prizm with 240K miles on it. It's well worn and well used. I installed some Bosche "Plus 2" plugs and noticed a very nice and noticeable power acceleration over the whole band. It wasn't super huge, but noticeable, even gained 3 mpg in town!! So if the 2-prong plugs did that to my car---because it burns the gas vapor better---would the 4-prong Bosche do better and give more power? I don't know. Haven't tried it. But wanted to mention that.