It depends on the type of data that you are trying to secure. If you are trying to protect a list of your favorite songs than you don't have anything to worry about. If, on the other hand, you are trying to protect credit card numbers or similar information than no it is not enough security. My point is simply that if the data you want protected is not worth a hackers time than it is safe. Another thing to consider is no matter what kind of security you use your data is still stored on someone elses server.

Joe