They actually even published a comparison of MIPS vs BrainShield:

The patch actually ruptures after an abnormally large impact. It is visibly sheared/ripped. This can be used by medical staff to alert after a large hit.

They actually have clear transparent BrainShield as well. It is basically invisible at 1 millimeter, same thickness of a dime coin. I found it on their website: http://shieldxtech.com/pages/gallery . I guess you can throw that on both sides.