Actually, all my 3 AFS 901s have gone to atty heaven (and I only used them at 3.7v on AFS).
I have one non AFS 901 which I purchased at the same time. I've washed it in Vodka twice and tried blowing steam through it from a capuccino machine steam wand. I still has the metallic taste, so the rusting argument makes sense.
http://www.e-cigarette-forum.com/forum/atomizer-mods/52074-check-out-steam-cleaner-attys.html
PLUS we have visual evidence from Vap'n.
One thing that hasn't been mentioned over rusing, perhaps because it's up there where angels fear to tread, is whether AFS is likely to expose the atty to more moisture producing rust, because the atty is surrounded by all that liquid.