I had the pleasure of having a white one driving alongside/behind me on the way in to work a couple of weeks back. Joined the A1 southbound at Biggleswade and stayed with me all the way down to the M25 junction at South Mimms, where I turned off and it went straight on.
I got all excited and tried to take a photo from my rear view mirror when it was directly behind me in traffic past Stevenage. Looked beautiful, sounded awesome. Unfortunately I was in my 'commuter car' rather than the GTV, which I do occasionally allow out for a blast down the A1 to work.