A con - utter waste of time and money.

 

Take a look on Youtube. There are plenty of videos about air intake booster claims. Will see if I can find you one.

Here you go

 

I agree, they look cool, but really do nothing

 

these devices do not add enough pressure to make a difference. i originally thought that a small one might be able to compensate for the air-filter's restriction, but it is sometimes forgotten that the engine intake vacuum is stronger than any of these devices. save money and optimize (tune up) the existing systems for a performance improvement. might just be better to clean the MAF. and do not put in a K&N air filter (just like a window screen) if you like your valve seats.