Pros : If you cut a lot of Zinc or Brass Came, you've got to get one of these. It is so much quicker, more accurate, and easier than the old craft saw and wooden miter box method. It's also fairly small, compact, and portable so it doesn't need to take up a lot of space. Once you have all the stained glass tool essentials, put this on your list. You'll love it.
Cons : I don't know why it is so expensive. There's not that much to it.
Other Thoughts : Gryphon makes some pretty good stuff.