Video DownloadHelper is much faster than most alternatives. It is reliable, though I sometimes need to reload the page to get it to connect to the needed video. Results are high quality (1080p, or the native resolution of the clip). The watermark is not an problem for me, but I have now purchased the license anyway.
[ADDENDUM] With the license, downloads are noticeably faster. Also, when a video site changes its download protocols, it seems that the licensed version adapts more quickly.

Good for local file downloads.👍
Cons: Doesn't work for URLs with "live" in the name.
Example:
www.youtube.com/live/jOd7XgeQ4SA

It would be nice if this were fixed.

Great app. You can easily set it up on Windows (same with Linux with a little bit of work). Very convenient when you want to download something for a road trip that may not have the greatest internet.

Ich benutze den Helper seit vielen Jahren und bin immer noch begeistert. Für mich gibt es nichts zu meckern.

Uma das melhores extensões que já baixei, faz com eficiência o que se propõe!

Très pratique et très fonctionnel !

Una de las mejores extensiones de Firefox, ¡lo máximo!

Ottimo per scaricare filmati da internet.

i have tried almost all of the download apps. This one is my favorite.

Great Tool

I bought this.