I do 3,000 to 4,000 miles per month of interstate.
I'll take asphalt over concrete ANY day.
Concrete has a MUCH rougher ( bumpier ) ride, as all the joints get out of whack with the winter/summer freeze/thaw. I HATE CONCRETE! I will drive out of my way to avoid it. The noise and bumps/jolts/vibrations at highway speed is intolerable... in Iowa anyway!

Since asphalt does not have "joints" and ashpahlt can "flex" it is alway a smoother ride ( for me ). Perhaps it costs more to the state and needs to be resurfaced more often than concrete??? Not Sure.

Since bumps absorb energy you need to replace with gasoline, I think anything other than perfect, new concrete is a dis-advantage.

My $0.02.
-John

Ditto

Steve

STOP terrorism - Drive a HYBRID

Vehicles:
350 miles a week ------------ 2006 HCH II, Magnetic Pearl, w/NAVI (born on May 25, 2006)
350 miles a month ---------- 2003 Mazda Tribute ES-V6
350 miles a year (for now) - 1986 Mercedes 560SL