I've been having this problem with metallic items in DAZ. I changes the maps, and all that other stuff in the surface tabs, but when I render it..it just looks like shiney plastic. It's lacks that sheen only metal has. I also don't have those pre-set shaders DAZ came with, i.e. metal, glass, stone...

one of the best things you can do to get the uber reflective sweetness of the shiney metal is set your glossiness to about 97%-100% and your ambient colour up from 0 depenting on how bright you want it.  then down in the reflection section set your reflection strenght to an area of about 75%-100% with a white colour ( 255 for all three or with a bit of a hue towards the colour you want reflected) then set your lighting model to glossy plastic i know glossy metallic sounds more like how it should be but you get the sweet sharp gleam from glossy plastic.

this is all in the advanced surfaces tab of course in any of the versions of daz

A reflection map also helps

yeah it usually speeds up the render with a reflection map but rarely reflects the surrounding items in the scene

The first example was achieved using a texture map.

The next image without texture map, some adjustments were made to the colors to give it a darker metalic appearance.

I have not tried using shader mixer as yet, but I am sure the results can be improved.

Here are some settings I used for the second image:

Diffuse:
    color = 255,255,255
    strength = 5.0%

Specular:
    glossiness = 80.0%
    color = 255,255,255
    strength = 95.0%

Ambient:
    color = 4,4,4
    strength = 10.0%

Reflection:
    color = 232,232,232
    strength = 80.0%

General:
    lighting model = Glossy (Metalic)

*note: it also varies with the lighting you are using too. So experimenting may be required.

Attached Link: FAST METAL Shaders for DAZ Studio

I used them on my last render "Seagod" for the statues.

Happy rendering.