For me, By all means,
Never buy from various ebay slingshots ,most of them are just re-sellers of fake slingshot makers,
they don't spelize in slingshot .
I 've found they have little knowledge of Zinc alloy and Steel. just re-sell it for money.
Only buy from the authentic Makers of slingshot.
The image I recevied from my HongKong friend who told me the big difference between steel and zinc alloy
is that zinc is very brittle which often lead to break or snap suddenly.
and steel could bend, say,put 1000000 pounds force on it , but it never breaks nor snaps.
How dangerous is the Zinc slingshot....