Hmm... Prepsol huh... we've got a Supa Cheap Auto down the road, I might pop in there this arvo and have a sticky beak.

I bought a batch of 50 Magic Eraser pads from China on eBay last month; so far they've proven to be great at cleaning mold & mildew from the shower recess which the wife is quite pleased about - mainly because I'm the one doing the cleaning ;) though I'm yet to try them on a PF.