I have the cat-back. It is only 2" piping. It's all stainless, it's high flow and very loud. Better performance than stock. Looks good on the car too. There are some issues with the hangers though. If you do a search in this forum for both the headers and the cat back, you'll find a wealth of info.
As far as being good, all Borla products are warranted for one million miles. I have heard the early design of the headers used to crack, but apparently they remedied this in the newer design.
[This message has been edited by Fred Zaplitny (edited February 13, 2001).]