I've been using it since SpeedDial stopped working after Firefox went Quantum. And this addon still remains the only good replacement for it. The problem with this one - when the browser starts sometimes there are no dials (no group), and I have to press new tab for them to appear. It also can't stay at the same group in a new tab (it switches to the first group), and most important, you can't save group as HTML. That cloud synchronization is of no importance for me - I don't reinstall browser too often. It is better to have HTML option - to open in other browsers or casual computers. But I still rate it 5 stars - it is the best of all of that kind. I tried its rival Russian-made FVD - and there is big difference - this addon is made for users by a real enthusiast and not for profit by all costs as the FVD.