Most of the bounty right now I guess using MEW, I'm sure this will continue to exist. Well we don't exactly know what ahead of us but if this thing happen there are alternatives in the market anyway. But I love MEW, I don't have any issue using their wallet.
Every altcoins that I have today since last year are ERC20 tokens so therefore I am only using MEW to store my altcoins.
I never face any issues and problems using MEW so I don't think it the wallet that won't work.
as it is proven that MEW is working - there are so many malicious attacks on mew website and they tried to copy the content by phishing technique so that they could steal crypto assets when users fall into their trap.