Gents,
I disagree with your logic. Look at it this way. Every bike needs spark plugs, gas, oil, an air filter, etc.. Unlike a new pipe, all of those things wear out or are used up each ride. They have to be replaced or replenished. If I were to replace the stock pieces with the best plug, the best gas, the best premix oil, the highest flow air filter, etc., all those negligible gains would add up.
I need a couple of new air filters. No one ever says to use the cheapest ones.
deadhead