These ads have been around for a while. There are different incarnations but basically, these guys get you to install aresistor or tank circuit in series with some engine sensor , either the MAP, MAF or IAT. This lies to the ECU and the car adjusts around it. Pure snakeoil if you ask me. That being said, we do similar things with SMBC, MBC and MBC+A on our cars but that's ok because I have one of those
(and their from a reputable fellow member on our board.)
But hey, if you get one ask him if he'll throw in a "Turbonator" and "Magnetic gas molecule straightener" at no additional charge. Heck, add in a No Fear sticker or a picture of Calvin peeing on a BMW symbol and you'll get like 500bhp.