Air Cleaner Question

There is likely a substantial difference.
D. Vizard did extensive testing of ACs to ISO 5011 standards. K & N tested against two similarly sized filters: K & N 440 cfm, others 378 & 351.
Not only did the K & N flow more , but it was more efficient at dust removal, 97%. Others, similar size: 50.8%, 93.9%, to as low as 25.9%. &