Ok firstly I should point out it worked for half a day after I made a PayPal Donation to get the PRO version in the morning then stopped working and asked me to make ANOTHER donation for the PRO version in the afternoon.
I am sure I am an exception rather than the rule and I have contacted them over the issue. I type this so others are aware there can be issues.

Having said that I now have it working again after being e-mailed an activation link following my complaint. I found the support to be be pretty good.
Had I not encountered the, albiet, temporary problem I would have given 5 stars.

Es bueno

Seems to be currently the only FF extension able to download 720p/1080p video, and only after a donation. So even though you're not required to pay, this uses the freemium model. Sucks though that the main thing I need right now for a project I'm working on is to download 480p video and I can't seem to find any program that still does that.

i use this plug in almost every day and it works great. every once in a while it will have a bug but over all the experience is excellent!

Great downloader, thanks for your good work. It is helping me so much to do well in my studies.