Cuore,
Here's a thought for you:
I have always had something niggling at me when I look at the pics of the quad exhaust on Autodelta's site.
http://www.autodeltashop.com/popup_image.php?pID=275
I think I have finally pinned it down. If you look closely you can see that the alignment of the pipes compared with the recess in the moulding for the OEM exhaust are out by a small margin. This makes the exhaust sit lower and look more 'on' the car than 'in' the car (if you know what I mean). The same is visible on the You Tube clip.
Now if you compare that with this pic (its about half way down under the heading ALFA156 GTA):
http://translate.google.com/translate?hl=en&sl=ja&u=http://www.canam.co.jp/csc-news.html&sa=X&oi=translate&resnum=3&ct=result&pre v=/search%3Fq%3D%252Bcsc%2B510283%26hl%3Den
This is the CSC quad and you can see that it is a much neater fit and since its overall girth is less, it fits in the OEM recess. Of course the other side has involved hacking at your plastic moulding but the finished effect is IMO cooler
That said, I would swap my left boll*ck for either system.
Cheers,
Gary
Edit: Here's a better picture of the CSC of an swiss tuners site
http://www.alfatech.ch/gallery/alfa/...6gta%20283.htm