I mean the Windows wallet offered by every small sample campaign like the bitdepositary bounty..
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I think all wallets are safe, when we can use them and secure all seeds, passwords etc. Where you store it offline in order to avoid virus attacks or intruders through online activities.
if you mean a Windows wallet which is only valid during the campaign and after distribution. when everything is done then as you said for example bitdepositary wallet, the reality is not visible in google search, support it with campaigns that are no longer visible.
Online wallets are only safe if you do no transact anything suspicious online and that’s not Etherscan since its just like a blockchain explorer and I think MEW are indeed safe especially if you choose the best option. I still prefer to have a wallet where I can really control the keys, hard wallet might be the best option and with regards to ERC20 tokens, choose MEW or other wallet like Metamask.