Rated 4 out of 5 stars

Overall, this add-on is really dynamite. I'm most impressed by the tremendously individuated views for each (you can choose to automatically scroll the percentage gain, daily $ gain, total value on hand, etc. of the center of your portfolio, while only viewing the percentage gain of minor stocks which you are only monitoring... awesome). It's also very customizable in a lot of ways (you can change which 3rd party site to view the details of the selected stock, and vary it by stock). And it blends it very nicely into the browser. Some people have complained of it causing the browser to crash, but I haven't found that to be the case.

There are only two features that this add-on lacks, but they (to me) are tremendously important.

#1 - I would absolutely love for this program to have a 3rd party database of stocks, like Foxmarks (or, more relevantly, Firestox) does, which would allow me to use the program on two or more computers without having to change my settings on each computer. I often add a stock to watch on one computer, but then I have to remember which I added to put it on my other computer. Having my portfolio online would be a huge plus, and the fact that it's lacking is really disappointing and annoying.

#2 - Mind-numbingly frustrating is the fact that, once I've added these stocks to my browser, I can't change the order that they appear. If, for example, I want all of my tech stocks to be shown in a row, I have to add them all at the same time, or else when I add one later on, it will be out of place, since I can't change the order in which they are displayed. I don't know why this is, and it seems like it would be tremendously simple to implement. If I knew code, I would do it, I promise.

#3 - I know I said I only had two complaints but this is minor. In renaming the stocks, one cannot use a space, meaning "Best Buy" becomes "BestBuy." Just annoying.

However! Overall this add-on is really killer and very helpful, almost ideal. Certainly the standard for firefox browser, but not yet perfect.