I’ve used plain old vaseline on the guides. Its worked for me.
It does need to be refreshed from time to time but its cheap, handy,
and doesn’t seem to harm my flylines.
Plus, I carry it as my firestarter(on real cotton cotton balls) so always have some, somewhere in my backpack.
Hugo
PS Yes I’m reading EVERY POST in the fly fishing section. If you mention Brookies in any way I’ll know!!!! And, I may email you too!!! hahahaha