Blitz exhaust and decat

Now the local garage has sold my old 7 without its Blitz Nur Spec and decat, he wants to flog me the system back for my 330.

Qustion is, should I do it. He wants £150 for the full system, it has only done 2000 miles before I sold him the car, but I have heard all sorts of stories about fuel cuts etc and I am worried about replacing the standard system on my 330 for the Blitz. I would have to change local garage as the Mtzi dealer I currently use wouldn't honour the warranty if I change.

And on the 7 the Blitz didn't appear to be that much louder. I think when accelerating it must have been, but I remember being disappointed when it was first fitted as I couldn't really tell that much of a difference.

And my 330 is going like a dream - I can't imagine a car being any faster - I don't track and I suppose an average driver, buts it acceleration is never short of awe inspiring!!

And the Blitz is smaller than the 5in standard system. And dosn't look as good.

So - should I? Has anyone else changed on their 330 and is there any difference on the 8 compared to a 7. Is it worth £150 for what is basically a loud noise!!