And tell whoever is mounting them to do so as well!
I just got some Chetlers and the store messed up mounting them by about half a CM. The factory was to blame (if you don't count blaming the tech for not double checking).
Printed on the skis are two big lines for center mount and factory mount, on one ski there were 10 hash marks in between the lines and only 9 on the other. They just decided not to print the 10th for some reason, leaving an extra large gap to the back (factory line). The tech just counted up 4 lines from the factory line on both skis and mounted.
Definitely should check every time, and maybe recheck.