I lived just down the coast from Olivers Mount and used to go and watch the motorbike races. I remember going round the course on my Honda 50.
I have also been round the Nurburging when I was stationed there in the army.
Comparing the two is as big a stretch as you can get. But they are both excellent in their own ways. Olivers Mount is quaint and countryfied. Imagine the Brooklands car racing scenes in Downton Abbey. The Nurburgring is the real deal. It massive, rolls everywhere and hemmed in by trees. Jackie Stewart called it the Green hell.