Im a fan of that set as I went through the mill trying to polish my rusty pipes and tried to get a re-chrome for a reasonable price-but no luck with that one. My rebuild was always going to be on the cheap as Ive a few other bikes to concern myself with-oh and them 4-wheeled things.
So, 9 years ago those kits came out and I bought and fitted one-its not a 1/2 Hr job as they either don't fit the head or wont seal-As said-theres only one retaining bolt but they are a decent fit into the collector box and a smear of paste does the job of sealing. I know this sounds heresy, but I had to grind a few of my collets down to get them to fit. The result was pleasing and I had nice shiny exhaust system as opposed to 3 rusty pipes with no chrome and a welded collector-box that was more weld than metal.
As I said, 9 years now on and yes, they have discoloured as they are single-skin, but they are far better than what was on there-even though I had a few rusty sets of pipes/boxes to mix n match.