Nice looking bot you got there. I love the detail on him - the texture sets the tone of him quite nicely. His form reminds me of Star Wars prequels robot designs somehow. Must be the lines and the texture.
Very cool. So looking at it again, did you go at it start to finish in Zbrush, or did you bring in another program? You ended up with some super sweet clean lines and shapes in it, that's something I can't stop noticing in it.
I started it in Maya with the plans to just do a really low res model with only a diffuse map, then I decided that I needed to learn the pipeline for creating bakes from a zbrush model. I brought the Maya model into zbrush and added a few details after which I exported it out and used topogun, Maya and Xnormal to refine the low poly model for bakes and to create backes from the zbrush model. After that I did the different material maps in photoshop...the rendered image is from Marmoset Toolbag.