From various sources, MyEtherWallet (MEW) are not under development and maintenance any more. Even its founders has confirmed that they are switching to develop a new platform called mycrypto and encourage everybody to move there property to there.
But IMO, MEW or mycrypto is just a gateway to access your real wallet in the blockchain, so, both of them are still fine event MEW is not maintained anymore, right?
Well, we don't know the features the mycrypto wallet will offer, MEW is still serving the purpose without much glitches. Avoid following unknown links that lead to MyEtherWallet interface and also keep your login details safe. With these, you are safe with MEW.