I agree that it's good to be wary about who you believe and where their interests lay, but I believe their numbers based off what I've seen from their programming and read from them in articles. They seem to know what their doing, and I have chosen to trust them. Whether or not other people do is up to them. I think a lot of this kind of stuff is splitting hairs, but that's the point. Trying to find how much of an improvement something makes and at what cost. And the extra resistance to turn the alternator will be nowhere near the resistance of a fan.