I've seen their math; also, 500 is the lower number they claim. Was told you can go further, to about 750 before loss of performance (the wheel isn't coded) sets in.
Their claim is that you should be refreshing your edges every time you skate, so if there's no trauma, one pass will do. 3 would be considered the extreme end of the cycle. Using the math above, if you go 3 passes x 2 skates x 500 pair, that equates to 3000 passes. 500 pair at $99 equates to $.19.