Just starting to gear up for the upcoming salt nook season and was wondering for those that use a classic style knuckle-buster mooching reel if you use any backing?

Seems kinda silly to me to fill my Shimano 4000GT with 500+ yards of 20lb mono. I use it a few times and have to pull it all off. Seems like a waste of mono.

Wouldn't I be better off filling half the spool with backing, and than slapping on 250+ yards of mono?

Just curious. Also, curious to know how the backing holds up to salt water abuse over time. Even after a fresh water rinse/dunk, there's always some salt left over that will get soaked in the backing.