No joke! Buy antifungal foot spray (the type you use on your foot or shoes) and spray your gauntlets and head-piece once a month (once a week if you practice every day) in the inside, but NOT BEFORE YOU ARE ABOUT TO USE IT, let it air for 24 hrs (I do it on the last Sunday of the month).
When you see white stuff on the outer surface of your armour use a medium brush to brush it off.
I sweat like a pig, and like everyone else I stink after a workout. I've had my bogu for 9 years and the smell is negligible.