[g.willikers]

Storing in cases is ok, with precautions.
It's important not to let the guns lie down flat in the cases.
Store them stock down instead, so there's space between gun and case.
Spraying the inside of the soft case with silicone helps, too, as does the afore mentioned socks.
Lube them liberally, in addition, and all should be well for many months, at least.
That's the way mine are stored in very humid conditions most of the year, without any problem.