Ks are better then miles for repeats. It doesn’t really matter what you use to measure total volume though. We do race metric distances much more often and tracks are all metric now. It’s just American runners like to brag about “mileage” to non runners. If you said I ran 100 kilometers this week you would get an “ok I don’t know what that means.” But if you said I ran 60 miles this week you get a “wow that’s farther then I drive.” Ugup ugup