I know... and I care too! I want my set-up to be reliable and in as good of condition as possible.hedoe said:i dont think that no one know or cares. but i would guess-to-mate that it is about a year or two.
It depends on how often you shoot. They do wear out eventually. Buy some bulk material and cut to length and keep it on hand. Replace as often as needed for your set-up.
Here's a great source...