I was trying to do some research on the new Cone Salt and Pepper workshirt and came across this site:
It would appear to be a place in LA that happens to sell a lot of the fabrics used by Gustin. I thought this was interesting as I always figured Gustin worked directly with the mills to obtain the material, but it would make more sense that there would be an intermediary involved in the process. This would also obviously explain the picture of the matching shirts posted above! Additionally it explains why on new items such as the workshirt they only post a small sample of the fabric and typically don't have a shirt made up in advance, they only need to post a picture of the free sample.
Just thought some people here might enjoy the above link, certainly seems to add some transparency to the process for myself.
Back on topic, I think that Salt and Pepper workshirt could look deadly, but I am having a hard time visualizing exactly what a made up shirt would look like.