I'm not an expert but I would think RB could be fairly stable if slabbed and kept in a safe environment. There was a long period of time this stuff couldnt and wasn't protected as well as they are now. Its amazing any red examples still survive of the early 19th century examples.
In one of his many books, David Bowers advised buying brown MS cents as a collector, and I agree with that. I wouldn't pay extra for full red cents.