Unlike May and Dawn, who generally got along with Ash and only argued with him in a select few episodes, both Misty and Iris generally made it a habit to argue and badger Ash.
Misty and Ash got into petty squabbles all throughout the early seasons. Although this stopped in Johto due to Togepi toning down Misty's character and Johto's writing being shot, we still had some of it like in the Totodile episode.
Meanwhile in BW, Iris constantly calls Ash a kid and berates him.
Whose arguments with Ash were more enjoyable?