I don't have direct experience with the Kimber aluminum frame Pro Carry, but I note that the Standard Catalog of Firearms makes this statement about the corresponding Colt Commander:
"The Combat Commander was produced in response to complaints from some quarters about the excessive recoil and rapid wear of the alloy-framed Commander. This model is simply a Commander with a steel frame."
Althought the Kimber is based on the Colt design, it is possible that the aluminum used today is better than in 1949, when the Colt alloy Commander was introduced. Aluminum is clearly inferior to steel in hardness and wear resistance, but is adequate for many applications and is widely used. If I were getting a compact 1911 for carry, I'd get an aluminum Pro Carry and not worry about the wear, because I like the 5 ounce weight savings over steel and I doubt if I would ever wear one out. For heavy range use and recoil absorption I'd stick with steel.