There is such a thing as chipping, in case you didn't know. Even if this thing on ebay is true, I wouldn't do it. The large % of the cost of chipping is the customer service you get with your purchase. I would be uncomfortable not having a place to service my dub if something goes haywire.
Wow...I want to buy one just to see what it is. A dollar per HP..hells yeah!! Actually I bet that $20 bucks supports this guy's crack addiction. I wish VW tuning was as simple as this. Just by their description of how it works; it's not possible. Our ECU is smarter than that (& him for that matter) and will make adjustments accordingly.
My favorite quote: "This mod does not void any warranties, and it will not hurt your engine or computer. You will not believe how easy this is to do! I put this on my vehicle and it works great!"
Stick with a reputable chip mfg. that can support their product.