Sorry, I know it's annoying when people don't answer the question!
But when the frequent replacement costs became silly I stopped using them. I removed the contents of an old filter and put a few glass marbles in their place for weight before refitting the base.
There was already a metal gauze particle filter in-line by the pump and many other new vans don't seem to use replaceable filters anyway, so I felt it was a reasonable thing to do. Used it like this with the usual regular sterilisation procedure after a long layup. Over 8 years no problems and everything was fine.