Straighten me out guys....but I just saw a picture of the underside of a Porsche that was running SSI headers and exhaust that's touted as being good quality stainless, and a product that enjoys a good reputation....and they were completely "rust colored" as Squerly described. I'm told that stainless just turns that color due to the heat over time...not because of the manufacturer used a cheap grade of the stainless steel.
1987 factory Slantnosed 930 Cabriolet/Guard's red
2002 Midnight Blue 996TT X50
1999 Iris Blue 996 (Dash fire burned and totalled 9/07)