DTA! is the BOSS of Addons. Rated 5 out of 5 stars
First off, I wish to take my hat off to the guy who signed up just to say that DTA! is what it is: the best download manager for "raw", browser-linked, FTP or SFTP, cloud, sea, desert-hosted, wherever they're hosted, files. Except of course for torrents. I would, given the choice, download a 15GB (OPEN SOURCE) game or educational film about the polka-dotted pigeon-fowl of Rwanda as a magnet->torrent. But if it were the same thing, just the choice was for the Ubuntu iso... I'd use DTA without thinking twice because the source I knpow to be reliable, and it will whip that 700MB-ish data package's ass in at most two hours. Probably much less. May DTA live forever as it is - one of the few rare apps that have stuck to their original recipe. And may the devs be granted entry to heaven for their humanitarian efforts. Amen,
As for https://addons.mozilla.org/en-us/firefox/addon/downthemall/reviews/434358/ - well, it's not noob friendly. Stick to the built in download thing on Google Chrome. No setup required at all.