[captain harlock]

Polishing is quite easy, actually. Some would use a Dremel with a polishing tip and polishing grease, but that would take time. I use a clean towel with the Mother's polishing grease and I got a very good results with the G-Maxx chassis and skids( very hard to polish). Titanium can be polished, but it needs a very powerful polishing grease and some experience to do it. The UE titanium skids comes unpolished and I was barely able to make them shiny with only a towel and Mother's grease. You can actually take your parts which needs to be polished to a real car polishing shops where they tend to polish car's wheels to a very high luster. I don't think they'll charge you much for it. It depends on the size and quantity of the things you're gonna polish.

I think your parts will remain shiny even after hard bashing as long as you're cleaning them oftenly. Ofcourse they'll loose their shiny state after a while, though.