Been at this 22 years, 21 years ago I threw away all fuel line filters, on both the planes and the fuel can. 60 airpalnes and nearly as many engines later I have never had a problem with dirty fuel. It may depend on how fast you use up the fuel, and I always keep fuel stored in a dark, dry, cool place and keep the jug sealed except when filling. I do empty airplane tanks back into the jug at the end of the day, still no problems. If I lived in a dusty area I may reconsider. By the way some of my engines have been around nearly 20 years and still start and run with no problems. Filters may be needed to compensate for other bad habits.