For what they cost....what 3-400???....probably cheaper to buy a new one every year then end up in the hospital with a busted leg, etc...
I tore my achillies tendon on my right foot slipping on the ice (not in my driveway)...hurt like a BLEPPETY BLEEP for a long time, and to this day it still bothers me from time to time....
Seriously speaking, it should last you 3/4 years I'm guessing. Builder is right though, even if you buy a plastic hopper version it wont be rust proof...only way to get generations of service would be to buy one made of stainless..