We did extensive research on book pricing websites and add-ons before hiring the expert add-on creator Baris Derin whose add-ons have been downloaded millions of times. He's done a great job creating a easy to use add-on with a pleasing interface. There are no known bugs or problems with this add-on.
Please note, though, that occasionally you may come across a bookselling website (most notably eBay) where the BBM tab does not automatically descend. If you encounter that, you have a few options. The easiest is to highlight the 10-digit ISBN and right click it (the 13-digit ISBN should also work just fine, but sometimes has a dash in it that prevents it from working properly); this will engage the pricing function. Other options are to click the BBM icon on the right hand corner of your browser (this icon appears after installing the BBM) and put in the title or ISBN in the search box that pops up. Both title or ISBN will work, but ISBN works faster.
We hope you enjoy using Bargain Book Mole as much as we do and will tell your friends about it.