Doesnt make much difference. The way you described it then yes it would be better as 5g a week will end up being more then 25% a month. It also keeps water parameter changes to a minimum. But your also disturbing your fish and tank alot more often.
i don't know it's fairly eay to do a simple water change pretty surreptitiously, unles you have very delicate and easily spooked fish i would think THAT would be as obtrusive as other maintanence, like algea scraping.
plus (at least when i see it) filter floss is like cotton sheets, i imagine they clog up like daily. the nylon or polymer floss is much courser of a screen like comparing a tennis net to a sand seive