The material is less important that the fit & finish + quality control.
Heat treat can be done right, wrong, or not at all, and it's impossible to tell visually.
Not a place to save money. Why? because the difference between great and IDK isn't that big, and that's one less thing you ever have to worry about. Valve train problem? It's not the pushrods.
Some look really rough out of the box, makes you doubt that anyone at the plant gives a $*@#?}.
Examine the ends - if you see radial rings (instead of a smooth glossy surface), those are tiny hacksaw blades waiting to eat your rocker arm.
Examine the tubes where the ends insert - any sign of cracks, fretting, wrinkles, stretching, cut not exactly the same place all around? Danger.