Yes, I realize from my research that there should be almost no savings from the Alternator, but I have got to think that there will be some savings from the Power Steering. At highway speeds (which is 95%+ of my daily commute) the power steering isn't doing much work at all. But there are still parasitic losses that will be reduced from under driving. To what extent no one seems to know.
I haven't seen any ABA tests for underdrive pulleys, nor have I seen anyone on this forum who has tried one. So it looks like savings estimates are just an educated guess. If there ends up being no savings, then I am out about $120.
