Sir, its true that Honda’s maintainess is expensive than other cars. But if someone selling filters at above prices you mentioned, then he must be making good profits.
Last night I checked Leppon’s air filter for Honda civic and guard’s filter at my friend’s shop.
And physical comparison showed Leppon’s filter paper was soft, more fluffy, neat, and strong also as compared with guard’s. My friend has filters of Leppon, OEM and Guard Company. He was running out of stock for CIVIC’s OEM filter, otherwise I would have compared that too.