I just serviced mine for the third time in 110,000. I see no reason to replace mine.
I've had to fix the starter button on our 2000 Tourer once. It has worked perfectly since then. The other 3 bikes have never needed it. I also did RedValk's 1997 Tourer a couple of years ago and it has been working ever since. Unless there is some component in the starter switch that is broken I wouldn't replace it. Just my .02...