the material is only 1 of many things to consider.

-What is the best lift/duration/overlap for your build?
-Are your cams designed to work with your spring/retainer/keeper setup?
-Will the company be able to provide YOU (not whoever you bought the cams from) support?
-Has the company been around long enough to make mistakes and learn from them?
-Does the company test cams enough to produce a good product?
-Did the company design these cams, or just steal someone elses R&D and copy them?

thats some stuff that matters