A quick google search seems to suggest i have to download the entire 16 years of bitcoin history from bitcoin core that may take hours/days??
Yes, you need to install the bitcoin core, and it must be fully synced because Armory will not work properly if your bitcoin core is not fully synced.
About how many hours or days it depends on your device specs it might take a few days or within a day.
Do you mean downloading the whole +600 gigabyte? And not just pruned by some extent? That's a lot resources to be considered, it will work just fine if stored in external drive right, or it should be installed in the device (computer)?