MT cloth is good stuff, though I just run them over with a simple none-abrasive cloth and some mineral oil.
It stays in saya and a sword wrap almost all of the time, which is very low maintenance.
Criminal, now that I think about it.
That said, even the naked swords on the walls don't want for much but the same treatment.
I've had more problems with other people's fingerprints than with rust.
I commissioned a full set by tosugu artist Roman Urban for this blade in particular... still unmounted as I'm unhappy with my current woodcarving ability.
Maybe I'll mount it soon, if I can stop beating up knives in the woods.