You don't realy need to replace your lense If you put something on your mask once. but if you kept doing it every time you got gogged it would be bad and you would have to replace them.
I am sniper,
user of smilies
answerer of stupid qustions
poorest paintballer on the planet
fan of comedy
person with least amount of friends.
AND NOW THE DEMENTED DICTATOR OF THE BAND GEEKS AND NERDS