The hardest lesson I've learned is this : metal abhors dithering (and texture in general). Dithering is funny because it can create a sense of smoothness over wide areas of close colors, but in close areas with a wide gap between colors it becomes shape-breaking noise.
Your helmet here works if you want it to look like it's taken a lot of abuse, but if you're going for shiney, suggest removing dithering and focussing on small, bright, sharp speculars with small, rich shadows to sell the "reflections". This will carve the details in a refined manner, and the eye will assume smoothness over the areas of flat color.
Thank you! I was going for the new shiny one, so you are very right and very helpful, I'm so grateful! Can you please point me to some example(s)?