My best wallet is a ledger wallet. Because of course the ledger wallet is very safe for me. Because when making a transaction requires confirmation from the ledger wallet. So I think it's safe and won't lose the assets that I have. But so far I've never lost my coin in MEW. I think it's safe enough if you use it carefully.
Many people use hardware wallets, and rejoice in their reliability. But it seems to me that today no one can give an absolute guarantee in the safety of their funds and personal data. In any case, first of all, our security depends on us.