It works well and I like it but it's not really an "extention". It's just a link to their website.

It Works BUT is very primative to save a Youtube video as audio you need to right click, then hit save as, then change name from videoplayback.mp4 to yourname.m4a.
PRO theres NoAds
CON it is very slow to download compared to others

Why this only allows to download at low bitrates? No 320kbps MP3??? Is it a youtube being strict thing?

Cut n Paste, 360p ok