I have used the bubble one for about 5 years now. Like it a lot. Have not had the fogging problem with it that some have mentioned. It has stopped some good size pieces over the years. Biggest one the size of a hot dog bun at about 1100rpm. Hit the shield about at my right eye area, bounced off and hit my chest, left a bruise for about a week there, but the shield only had a small scuff on it. I am a believer that it works.
Corel Draw 9, 12, X3 Also a CNC Router user. Web page http://www.scrollsaws.com