Definitely not, unless you have encrypted the file with good strong password.
I would not trust any cloud. Use cold storage for it. Any online use 2factor.
Some offer SMS/google authenticator which add another level. Also use decent passwords, and DO NOT use the same passwords. If you use different passwords for different places chances are less of worst case scenario.
If you use a deterministic wallet you don't need to store the keys anywhere as long as you can reseed the wallet. In the case of Armory, for example, you can make an M of N wallet where you would need M of N pieces to restore the wallet. You can make it so you need 3 out of 8 pieces and scatter the 8 pieces around the world - most people can't break into 3 locations to get your coins. You can even put one of the 8 pieces on the cloud - it would be meaningless for anybody unless they were hellbent on targeting just you. So cloud/online can be safe as long as it's not able to recreate a wallet in its entirety.
I can't see a justifiable reason for spreading out your coins into multiple wallets unless you're so well off you don't want people to know you have 10K coins, and in that case you can have your Butler do it