constantly failing.

All too often the downloaded video will be of 0 bytes; failure rate can range from 20% to 100% (in 10 videos).
At times when other addons didn't work, this generally did, but it fails so often now that it can't be relied upon, so I can't recommend it currently

MP3 Downloads nur als Premium möglich

only works for free on "popular videos."

very limited video quality for download (currently the advertised 720p is also removed, so only 360p download is available), as means to push for pro version. I am disgusted by this type of abuse to the community. It felt more akin to a scam than an honest add-on

Does not work

Działa ale za FullHD chcą kasę.

it didnt work for me,
hope to fix at the next updates

Doesn't offer 1080p separate video/audio downloads which decent players can work with fine. Instead, requires a premium account to "convert" them.

Since it wants money....