My car is 4 years old and only done 35kmiles and just had the S1 service listed below. i went for the 3+ age plan, I am happy with the monthly cost, also it does help with future value if it has main dealer service history. It doesn't include the timing service, but I will cover that at the time.
I pay 41 pound a month for a service plan with main dealer. It is pricy and that was with a good discount, but when I have taken my XF (RS) to independent garages, some wont touch certain parts!