I think the correct way to handle this is to always set a key. When I try to render some list items without a key I get this warning in the console: Warning: E

I think the correct way to handle this is to always set a key. When I try to render some list items without a key I get this warning in the console: Warning: Each child in an array or iterator should have a unique "key" prop. Check the render method of `YourComponent`. See https://fb.me/react-warning-keys https://fb.me/react-warning-keys for more information.