Its a chav mod for noobs to do, nowt more.
All it will do is make a really loud poor noise (on a ******* diesel) and be nasty.
A good exhaust note and noise is down to many things, engine (obviously), headers, pipe sizes, cats and of course mufflers.
This thing will sound absolutely and utterly garbage, its got a DPF and turbo in the exhaust track which is always going to make it sound crap, plus diesel almost always sounds utterly terrible for an exhaust note.
My 5 has a straight through (not headers yet) exhaust going to a 4 tip muffler and sounds bloody great when it gets opened up to its new 7500rpm revlimit, a crapbox 1.6 diesel is going to sound mince at its top end of 4500rpm lol.