Armory runs on top of Bitcoin Core so you will have to install Core and let it sync until you can use Armory. Armory was the first bitcoin wallet to provide cold storage using a watching only wallet on an online computer, with the signing wallet on an offline computer. You used a USB drive to shuttle transactions back and forth to sign and broadcast.
Armory was always a bit of a pain to use and update, and when Trezor came out in 2014 most everyone who believed in cold storage switched to using Trezor. Then Ledger came along. Now hardware wallets are popular. Armory, not so much but it has some diehard fans who still use it. It is still the most private way to use bitcoin and security is the same as Trezor. Just not as convenient. If you already run a Bitcoin full node take a look.
Electrum is probably the top bitcoin wallet available today. It has good dynamic fees and you can send replaceable, so you can bump a fee up if needed. It also supports all the common hardware wallets. Hard to go wrong with Electrum.