Really liked using this tool as it solves many of my work organisational problems. However, as others have mentioned, at least in Firefox, it loses tabs FAR too often. It will open them, but when you click on a tab it just resets to "New Tab" and that's it, work lost.

I can sometimes recover them from the history, but if I have to spend time managing my tab manager, there's no point.
Sadly I can't rely on this tool as long as it has this problem.