I actually drove a 2007 XKR convertible today. I was looking at the coupe, but the convertible was they only one they had on the lot for test drives (figures in my neck of the woods). Aside from the exterior paint, (indigo vs. radiance) it was the same car as in the OP, including the 20 inch Senta wheels.
The car is predictably smooth and docile until you really step on it, then it goes like a scalded cat. It's beautiful to look at and the interior is comfortable for the front passengers (though the rear seats are unusable). Still, the interior doesn't bowl me over like a car pushing almost a $100k should. I usually like aluminum finishes, but on the XKR they use a "waffle weave" meant to evoke the look of carbon fiber. To me, it evokes the look of tin foil.
I also had a hard time getting a good seating position, but that was more a function of lack of time to fiddle with all the myriad adjustments.
What I really noticed about the car was how long it is in front, you sort of feel like you're steering a boat from the wheelhouse if you know what I mean. Yes, the classic GT style is the long front nose and small passenger cabin in the back, but it's really pronounced on the XKR. I just checked and the XKR is longer than my wife's sport-ute, a truck that seats seven, so you are talking an awful lot of metal up front considering the Jag really only has two front seats and a small hatchback.
Also, the car is not only really low, but you sit low in it. You feel surrounded by sheet metal and that's not necessarily a good thing when it comes to sports cars. I don't mind sitting low, but I like more visibility when the semi-trucks are filling the next lane. Maybe that was also a function of not having time to select the proper drive position since the seat height is adjustable and there was plenty of head room.
I think they're looking to blow the 2007s out since the salesman was eager to give me a test drive even though I drove up in my Infiniti G35, which is less than half the price of the XJR. When I told him that my lease isn't up until December, the salesman offered to cover my last three lease payments if I made my purchase before the end of the month.