How would you rate the cardboard flip holders? Is the thin plastic in the center okay for the storing/holding of both coins as well as chips?

It would also be very helpful to know which storage items in particular, made with the Polyester(MYLAR) mentioned, are best for the storage of coins and/or chips. I ask because I know nothing about this and would like to. I also do not believe I am the only one and this information would be helpful for others as well.

Thank you both very much for the information as well as education.