i am with scott on this.....
with my commercial mentor raising queens and experimenting and lots of nucs/hives passed between us, i inherited some of his plastic frames, now i know why i inherited them but.... be it accident or not, i have cycled them out. like scott said, never had them warp like the video suggests under normal conditions. i am not speaking of the plastic foundation, i am speaking of the plastic frames the foundation is in. i don't like plastic frames. they are not as durable, do get a little wonky, and are too flexible and as scott said, the ears break off, you have to trash the entire frame.
keep in mind everyone, we are helping out a new beek deciding whether or not to purchase these. zweefer, just go for wooden frames and pierco waxed foundation, or beeswax. you won't regret it. wood frames last a very long time, can be repaired, and if you are using plastic foundation, and the wood frame gets trashed, pop out the foundation and put it in a new frame, good to go.