Uni-Frame's Acceptablity
 

Has anyone ever used Uni-Frames or Fast Frames with their pastels?

Are the bracketed with string tension backs, type of framing systems ever acceptable for shows? I worry about the exposed glass, but this is such an economical way to show my work with a mat.

If you are not familiar with this type of frame, the link to follow provides a description.
Uni-Frame Information