Filter are most likely fine. They were not packaged well and two of the four have crushed corners. I don't plan on using them for three months since I just used my last Merv 8.
We had a Trane electronic air filter and a Boair electrostatic 1" filter. Replaced both with a Filterbuy MERV 13 20" x 21" X 4" filter. We saw immediate improvement in air quality and dust removal. My wife's noses was always congested and she was light headed. If we were away for a few days, she would feel good until she returned to this house and all her problems would return. . We thought the duct work was leaking and pulling in dust. The other filters were not removing the dust, just recycling it!