Pros : The tool comes with a little instruction card to help get you started.
It's lightweight, and easy to maneuver across the glass edges. I haven't had to reapply tape to a single piece, or use a fid to finish the job.
Cons : It's made of plastic, so it gets scratched by sharp tape corners and glass edges. Not a huge deal, but over time it develops some pretty deep groves which can cause indentations in the tape face.
Other Thoughts : For projects with many pieces, this is a great way to save time and wear & tear on your fingers.