[aerohead]

Its a good question and all I can do is relate what I experienced with the CRX.Michelin was touting their Green-X tire in the mid-nineties.Claims were maybe 4-5 % better mpg.They were not available in 13-inch wheel,so $1,000 later I had a set of 14-inch alloy wheels off a CRX Si and Michelin's new wonder donuts.The whole thing was a bust! I never experienced better mpg,either with the low-rolling-resistance of the tires,nor the reduced inertia of the lighter alloy wheels.The tires did have excellent wet and dry traction,not a bad reason to have them,but never delivered on the mpg promise.So all I can say to you is that the experiment didn't work for me.As to the wheel-covers,I did a post installment on Wheels/tires/wheel-covers.It may have some data for you to think about as to what you might expect from a set "of MOONS".Hope it helps,Phil.