I was amazed by how cheap the M6 was to insure. I was paying £105 per month for my 996TT X50 (annual was about £1100) and changing to the M6 lowered the payments to £55 per month!
Norwich Union (mine is via a broker, not direct) do trackday cover at £156 per day, with IIRC £5k excess! Seems very expensive until you look at the alternatives!