Armory has features that can help your wallet be more secure such as key stretching (to help fight the use of GPus to Crack the key should it be captured giving you more time to create a new wallet and getting coins safe) that and no relying on a server to process your transactions. Electrum however is still a great choice for those who don't want to take up 32gb and growing space for two blockchains one for bitcoin-qt and one for armory. For most security armory over all. Both would be just as easy to spend and eviscerated coin.