I am firmly in the not worried about wear crowd .
What I have noticed with aluminum checks is they don't seem to stay on the shank quite as well as copper does if your using a harder alloy . I had this same issue back when you could still brass checks .
What it boils down to is i get a "flyer" a little more often then I used to when using copper and on occasion I'll find a shiny gas check in the lane between bench and berm .
Don't take any of that as me bashing aluminum checks , I haven't bought copper since sage started selling aluminum.