Mate 0W 5W10W 20W gives less cold start up friction. W stands for winter so if in Victoria during winter it would work out okay the -40 would be fine as it reduce friction during hot condition or when engine produce heat since it is a turbo and I'd suppose would get hot so having 0w-40 would be okay but might not work that good during summer as I think 10w-40 or 15w-40 would be better during that period depending on what state you lived in.
5W-30 is good for winter as the temperature is roughly between 12c to 20c during the day and anywhere from -1 to 8c during the night in stand none turbocharged cars as the engine don't run as hot
10w-40 or 15w-40 is good for summer driving and if you live far up north in a place like Cans Qld where it is extremely hot and humid weather Probably better off having 20w-50..
Recommendation on oil velosty is only recommended as standard basis but depending what part of the country you live how cold it gets during winter and how hot it gets in summer. I've experienced in cars that starts perfict during the summer but was hard starting during the winter. Soon as I change the oil to a lower velosty my start up problem went away.
