I guess this begs the question - how heavy are they all, combined? They'll surely affect (cringe) the gas mileage, and possibly the performance of the truck (by weighing it down). One good thing, they'll lower the center of gravity, besides protecting the soft, naked underbelly.
Great stuff though - and regardless of mileage or peformance concerns, I know I'll be picking up a set of these.
Nice work guys!