It´s not easy to rate this particullar Firefox add-on. On one side it´s really usable gadget, helping to download vidoes from YouTube without bigger problems. But it has some "but"! After first few downloads on 1080/720p you start to realize, that was only a bait, beacause next hi-res videos can be downloaded only in payed add-on version! That´s a shitty trap. But when you aren´t too lazy, it´s possible to find a way to go around this unpleasant money launder. Every time, when you´ll make about 5,6 downloads.. or simply, when you realize, that no more hi-res downloads are possible without switching to payed version, you can simply go to Firefox settings and delete cookies and similar. Nothing more. After this step, the software can´t realize, you are behind the "free" bait and let you download next load of videos with good 1080 or 720p! And when you download really a lot material, you can every time make the same thing, during 3-4 clicking cleaning the cookies in settings and start downloading from starts again. I am too lazy to test all the YouTube downloaders in add-ons, to find if someone is able to download free unlimited amouint of videos in high resolution. Also i let this one active and after each 5th download, click to settins,(2nd) click to cookies, (3rd) clickto dlete them and that´s it. Few seconds, three clicks and next at least 5 downloads possible. Not so high price for the chance download every YouTube video i want. But now, i don´t know if i can reccomend this add-on. I managed to use it as i need, but don´t forget,the main idea is let you jump on the bait and then stop to make quality downloads or pay! And that´s not what i like.