I'm learning that just because you think something should use the StrongGrip mat doesn't mean it uses the StrongGrip mat. Had I tested small squares of these on the LightGrip first, I wouldn't have this mess on both my StrongGrip mats. One is photo paper, the other is cardboard that came in a pack of Cricut cardstock. Neither worked well on the StrongGrip mat, as you can see.
It's interesting that when you pick a material, Cricut Design Space will tell you what type of blade to use, but it doesn't mention what type of mat is best for that particular material. That would be helpful.
The fastest way to get these two media off my mats is to use soap and water. I thought I was going to have to leave them to soak, but they only required me to run water over them for about 20 seconds. Then I was able to push the media off with my nail. I decided to take it off faster with the spatula tool, though.