Just an observation, I have gone ahead and used the deoxit gold on both of my SS GGTS's. The buttons now have a different feel to them that I really like. The deoxit gold is filling in all the gaps in the button housing and there is no loose feel to the components at all when pressing it. It almost has a solid noise when pressing the buttons now. I don't think a better button spring would make a difference in my case because I feel that the deoxit gold is allowing all the bits of the button to make a great electric contact with each other so it is not relying on the spring to transmit current as much. From my second link about deoxit gold "These products are initially non-conductive liquids, when subjected to an electrical field, DeoxIT® and DeoxIT® GOLD promote current flow".
I think that where better springs would make a difference is for those that don't have the fuse upgrade and are relying on the battery post spring to make a contact to the negative battery terminal (In the stealth model for example), and for stock button springs where deoxit gold has not been used. As for the fuse springs, they rely on the built in resistance as a means of heating up under load and burning out or collapsing when a short occurs. If these were to be plated, their resistive properties would change and possibly stop working correctly. The only way to improve their connection inside the fuse post would probably just be to plate the ends that make the connections inside the fuse post, but again I am accomplishing that connection issue with the deoxit gold. Of similar concept is how people have sanded the bottoms of their fuse springs for a better contact area.
As a note for anyone that may try the deoxit gold, I would stay away from the positive battery terminal inside the GGTS. On my stealth model, my positive pin had become a bit loose, and having the spray applicator, some of the deoxit gold was able to migrate into the atty connector. Let’s just say it tasted awful, and I had to clean out my atty and connector and I don't know how unsafe
vaping deoxit gold is for you. Plus as Imeo said, the battery contact is polished nickel and has great conductivity anyway.