Welcome to the Bunnings Workshop community @ALAN2. It's a pleasure to have you join us, and many thanks for your question about water dispensers.
Would you please be able to provide our helpful members with a little bit more information about what type of pop-up water dispensers you were considering? Were you perhaps referring to a pop-up sink waste? If so, then the only real difference is in the styling and finish and whether you need one for a 40 or 50mm waste.
I'm keen to hear more about the product you are after advice on and assist further.
Mithcell
