I suppose if the mileage increase is just an icing on the performance cake, a 5% - 6% improvement is great.

But it is not enough of a reason to do the chip upgrade for just a mileage improvement. It would take 5 years to just get to the payback point of the $400.00 upgrade, based on 1 tank of fuel per week at $1.90 per gallon.

Bummer....