Dumbest question ever. Just because Runner #1 is running more miles per week, doesn't mean he's running a better quality of miles.
Maybe Runner #1 is jogging all 40 of those miles and is so naturally fast that he can bust out a 4:15 without any formal speed work, while Runner #2 is putting in tons of work on the track and yet cannot get any faster. In that case Runner #1 is way more talented.
There are too many variables to consider. You can't look at "mpw" and infer anything other than that the runner covers that much distance in a week at the minimum pace that he considers to be "running".