Rated 4 out of 5 stars
I like this addon and think it's very useful.
But I give only four stars because it could do with a bit of improvement.
First, I'd prefer to be able to put the button where I'd like to instead of having it fixed on the addon bar.
When it comes to toolbars, I prefer to roll my own; I believe this is an intetegral part of the concept of Firefox.
Second, the URL in the info (http://lazarus.interclue.com) is wrong (or outdated) for at least four months now. I guess its time to have it changed to the right one (http://getlazarus.com).
When those two things are fixed, I see no reason not to give five stars.