Pros : This is the most useful face shield support I've ever seen. You can cut the glass to any dimension you wish and the glass won't scratch as easily as acrylic. I purchased a super-sized magnifying glass and am using that as my glass shield. It fit the support perfectly. To get it into focus, I was able to raise the grinder a little by placing it on a board.
Cons : The shield's design allows infinite possibilities for creative ideas. If I could change one thing, perhaps an adjustable support would result in a perfect product. However, it's very easy to just raise the grinder if the support seems too tall.