I got a Cup-A-Cake container and decided to submit it to a rigorous daily testing routine. I put a cupcake with the sticky marshmallow frosting in one and threw it in my bag, upside down. Over the course of the day I dug through my bag for keys and my phone, the bag was tossed onto couches, floors, and the back of my car. For good measure we played catch with the unopened container and even kicked it about a little (we were sort of giddy from hunger). It was even accidentally dropped onto a hard tile kitchen floor. The cupcake emerged with a few crumbs on it* but otherwise completely intact, I’m very pleased. The plastic is a nice heavy weight and there is plenty of room for mounds of frosting. Of course, I’ll have to do more testing with many more cupcakes.
*Which very well may have come from opening the container to peek inside a few times during the day – a few plastic parts do stick into the side of the cupcake to keep in from moving.