I've got Exaltos, too. Love them so much I not only put them on my and my wife's older Volvos, but also put them on, right away, as soon as my daughter took delivery of her brand new 2007 S60 2.5T. I also upgraded the size on her car (as I did on my wife's and my own) -- for my daughter's car, I went from the OEM 205/55-16 (MXV4's, btw) to 225/50-16 (exact same rev/mile, according to Michelin's specs).

They're as sticky as hell -- these are W-rated (as indicated by the load-speed designation, even though the size includes a mere V in the size nomenclature -- i.e., 225/50VR16). It's noteworthy that high speed tires, being stickier, notoriously use more energy as they roll, and that would account for your lower mileage. All the "high-mileage, fuel economy" tires are much harder rubber, and that's their trick. You should know that you have to choose between traction (braking and cornering) and fuel economy.

These Exaltos also have a thickened part of the sidewall near the bead, to protect the alloys from "curb rash". Perhaps that's what's rubbing? On some suspension or chassis piece? You didn't explain clearly what part was rubbing.