I am a newbie in using ETH so I am using myetherwallet only. I have never tried any other eth wallet but I guess mew is very user friendly. I am not very sure in its security though because it is online wallet.
It is not a typical online wallet like Coinbase where you don't own your private keys. But in myetherwallet you actually own your private keys and it can be connected to hardware wallets trezor or ledger Nano s for advanced security.
The main problem is with phishing sites which looks exactly like MEW with a slight change in domain made to steal the user's funds. We must really be careful when logging in to MEW