What is Reddit's opinion of Mentor.FM?

From 3.5 billion Reddit comments

http://mentor.fm is awesome. Thumb up and down and it learns, without repeating (much) like other websites. Requires Facebook and Deezer. You can use free Deezer on desktop, but then sound quality is just 128 kbps MP3 (versus 320 kbps MP3 for subscription, I think).

For how to answer IIL questions, see:

[IYL] finding music, [YML] these tools linked below

For how to discover new music in a fire-n-forget fashion, I prefer:

Mentor.fm

edit: a letter