I saw it again on the M6 in Lancashire this morning, only it had broken down and was on the hard shoulder. A man was sat on the grassy bank looking a bit sick...
When I filled up with bio a bit later I was chatting to a guy with a Disco who said that there was an R8 cop car knocking about. Google failed to confirm this.
And I saw another one (in silver) a couple of days ago when I took the lad to school.
I'm not having one now, they're too common and break down ;)