Depends how many miles you do, I was doing 40k miles a year, 30k of which were in a 4 months period, I needed to have a good sound system.
Not one that plays really loud, but one that sounds good when played at normal levels, and that is what is tricky in a car.
I am only doing 20k miles a year now in my main car, but still want a decent sounding system that I can play my music on, and DAB so I can listen to 5 Live clearly.
Nice to here the XKR was pretty good, the Jag thing is an itch that needs scratching and decided on an XKR last week.