I had been looking for a good PDF editor in linux for a long time. In addition to a bunch of my favorite features, I was searching for a product that is stable, fast and is easy to use. Among the host of features, I was particular about highlighting, graphical annotations, comments and baloon notes insertion capabilities so I can very easily highlight, mark and add review comments to tons of research papers that I read and review regularly. The first tool that I tried was "pdfedit" obviously bec...