Paper wallets can suffice, but it entirely depends on your threat model. If you're concerned about them getting damaged or destroyed via fire, water or anything that could potentially come in contact with them, a metal wallet tends to have higher security based on that. However, the major concern would probably be physical security such as theft. If it's safe from theft, then the other outcomes are relatively low.
However, this depends on your current arrangement, and whether you're storing them in a house that's prone to flooding or has old questionable electrics. Only you can really determine that, otherwise you risk compromising your security. If you're storing your paper wallets outside of your house, then look at the environment you're storing them in, and decide from there.
The only thing that really makes me feel unsafe with paper backups, is the fact that the ink could fade after 20-30 years.
so the best is to go for the metallic sheet and got it encrypted
Hello! what exactly do you mean by that ?
Perhaps he was referring to stainless seed plate, you can read it here:
Stainless steel Bitcoin Recovery Seed Plate.
Yeah, I think paper wallet is suffice, but as @Welsh mentioned you have consider several factors, might be good to have a safety storage box for your safekeeping in a bank if you can have that option as well.
Just remember though that it's not 100% guarantee, this kind of setup has it's drawback and you really have to prepare for the worst situation.
Absolutely! have you got any ideas that about a better setup? It seems to me that it was the only option I had.