Phew, I was hoping you'd turn up and set these guys straight oilman

With my next oil change Im looking changing from Mobil 1 to Silkoline Pro S as I've read somewhere here that you rate it slightly higher than the Motul 300V.

What is a good grade to run mate as I live in New Zealand and we see temperatures ranging from 10 Degrees to about 30 Degrees maximum all year round.
I dont race my car but I do drive it rather quick when I'm out and about.