I used Pierco since 1987. The first were brittle and ears broke. I worked with the original mfg. and improvements on the molds. Bees do love to burr comb plastic if your bee space is wrong. I ran a lot of wood frame with Pierco mid rib for this reason. I always used wax coated but saw thousands sold bare. Supers with all Pierco frames will run an average of one lb. more honey per super than wood and wax. All comb building needs a good nectar flow. Most complaints about plastic stem from folks mistreating it befor they give it to the bees. It is dirty or dusty, put on hive with no nectar flow or other practices that would have totally destroyed wax foundation. Then the beek wonders why it won't work. Just because it survives his treatment, he can give or sell it to someone else so they can also have a bad experience with it. Is competitor made in USA? I have a problem with folks that COPY a product that Pierco spent years perfecting.