Ford focus mk2.5 zetec s exhaust

[Jimmyapage]

Hi I've been looking at a custom exhaust for my 2l petrol zetec s mk2.5 and came across Piper performance pre made exhausts on deamon tweaks had a couple of questions;

Has anyone used these or fitted them before I assume they are a straight swap.

How do they sound?

And with my zetec s body kit will I need the standard and ms rear bumper designed one or the st designed one. 

Any help would be great :)