Upgraded with Alpine all round inc tweeters jvc head unit.
Sounds so much better.

Simple upgrades like this can make a massive different to the overall sound quality. The OEM headunit is cack in comparison to even budget head units today.

As Gunzi says the weakest link in the standard coupe set up is the godawful Clarion stereos.

Absolutely!

I have a pioneer head unit (http://www.pioneer.eu/uk/products/archive/DEH-X8600BT/page.html), subwoofer (TS-WX110 I think) in the back wing, and a set of Rainbow components up front and 6x9 in the back. Very good sound for about 400 EUR all in. Even compares pretty well with the Premium B&W system in the XKR, plays the obvious and MP3s off an SD card and has BT connection to the phone. And does not look completely out of place in an 18 year old FIAT.