I havent done it on the Trophy but i did do it on my old clio.
Best places to to it are under the carpet in the boot, in the door panels and the rear quater panels, if you want to go all out you could then put it on the floors.
I makes a big difference, but TBH i much rather hear the engine note.
As said before I used Brown Bread which was excellent value for money and was really easy to fit, you will need to take the door panels off to get a perfect fit, And always keep any cut offs you have, they come in very usefull.
Best places to to it are under the carpet in the boot, in the door panels and the rear quater panels, if you want to go all out you could then put it on the floors.
I makes a big difference, but TBH i much rather hear the engine note.
As said before I used Brown Bread which was excellent value for money and was really easy to fit, you will need to take the door panels off to get a perfect fit, And always keep any cut offs you have, they come in very usefull.