Gewehr98, I have the stock chrome heat shields on the bike. I've even replaced them after the clamps broke off.
It's the area on the pipes between the heat shields and the mufflers that's turned brown. When I compare my bike to a new one, my exhaust system is the most obvious indicator of age. Next is the seat which, while in very good condition, is an 80's style seat.
I'm pretty particular about keeping my bike in good shape. Before EPA regulations drove the cost of chroming through the roof I'd get my header pipes re-chromed. Cost was about $150, but now would be three times that.