I was wondering what engine oil you guys use in your RST's. I've got a S1, that I've not owned for long, in need of an oil change. Think its running about 190BHP.

Halfords recomend 0w - 40 oil
RS specialist says this is too thin and recomends fully synthetic 15w - 50
And Fords say this is far to thick get a 5w - 30 part synthetic

Any help would be appreciated.

S1Luke