I've only been to the Kalamunda one, thats good. Gotta get out to some of the others, i'm sure there'd be something unique about each of them.
I go to Coventry Village in Morley. It's not really a Sunday market, so I didn't really think it was worth replying.
Kyilla in North Perth has a nice Saturday morning showing. There used to be a food van doing great bacon and egg rolls. Perfect for chewing on while wandering over to the fruit and veg.