Several years ago, I examined a wonderful Bali-Song Cutlery custom with elegant pre-ban genuine Ivory inserts that had aged to that wonderful cream color that real ivory ages to. No cracks or splits. Just a flawless, the ivory, the handles, the blade, a wonderful piece... until you turned it over. The ivory on one side was stained green! The owner explained that he'd kept if for years in a cabinet lined with green felt. The dye had transfered to the ivory and ruined the knife. I've since been told that this problem is common with typical "craft-store" felt and that bone, stag, horn, and even unsealed wood can all pick it up. The problem is far less frequent, but not unheard of, with other fabrics too.
Now, this isn't a problem for a knife that's going to sit on a cloth on your table top overnight, even for month. But, it's a concern for long-term storage and display.
If you're gonna keep a knife with a susceptible material on a piece of felt or cloth long-term, then you need to use museum-grade felt or cloth.
I don't, of course, know anything about the felt that may be in any particular chest or box. But, if you don't know the details about it, I'd suggest not using it for long-term storage of knives with succeptible materials.
Foam is nice for short-term use, especially for transportation since it cushions so well. But, it can trap moisture close to your knife which is not good. So, I'd caution against foam for long-term storage too.
If you're privileged to own one of the BM49-SPLs, I'd actually suggest storing the knife outside of it's presentation box which has a die-cut foam insert.
My long-term storage of special knives are now almost exclusively in custom made cases from Bill's Custom Case. Bill is just great. He even made a "baby Bill's Custom Case" for a special miniature balisong I have. But, if you're not privileged to know Bill personally, well, you can get standard Bill's Cases from Texas Knife Supply. The materials Bill uses are specially selected to be ideal for long-term knife storage and the workmanship on his stuff is always first-class.