Have a set on the Road King.
They have a sixties type muscle car rumble to them instead of a blat. Helps on long trips / touring.
Decided to go for the S & S as they are the same price as there main competitor and are made from polished stainless steel instead of mild steel and chromed which helps if you scratch them.
Apparently you can purchase different length baffles that are easily changed over but I'm happy with the present ones in my mufflers whatever length they are.
Hav'nt had any cracking issues with mine so far.
I have a set on my 07 streety they have a great note about them & I also have a set for sale in very good condition.
Here is a link for some pics of the pipes.
http://www.hdforums.com.au/Default.aspx?tabid=71&forumid=9&postid=176024&view=topic