I am keeping my coins in three ways - exchanges,MyEtherWallet and hardware cryptowallet Ledger Nano S .Sometimes it takes time to move tokens from wallet to exchange and I am having some of my funds at the most famous and safe exchanges such as Bittrex and Poloniex.
Good choice mate, well I am only stored it in MEW, not because its free bit also easy to use. Just be careful with your private keys. Never ever give it to anyone. Because hackers are just around, they will to try hacked you if you handle your keys carelessly. Be carefull mate.