On topic of tanks etc, I've always wondered why brass tubing are still used... exposure to glow fuel makes it go green with time, forming a slime. (I'm using good quality fuel and mostly Dubro tanks). I've had a couple of tanks where the brass tubing became brittle and cracked lengthwise into "slivers", almost like glass splinters.

There are now tanks available with a plastic screw type stopper with fuel type nipples already moulded in it. It works so much better - no brass needed but these tanks are very difficult/scarce to get.

Why not use stainless steel/aluminium (one get it with some tanks) or above plastic nipple type stoppers?. Is it a matter of cost or just tradition?