I'm assuming the cage platform isn't resin...
I'm assuming the cage platform isn't resin plastic, is it painted cro-mo or anodized aluminum?
Nope, plastic all the way. I can't say I've never seem them fail, but generally they stand the test of time. They do make an aluminum version, but the cage is silver on those.
I googled "1/2-inch clipless pedals", and these came up among others. Are they actually 1/2-inch spindle pedals?