The jury is out on V-Power but after splashing out on a special car like the ST I can't understand anyone saving a few bob by sticking cheap supermarket fuel in. I always go for proper branded stuff like Esso or Shell even with a standard car like mine.
As for the first oil and filter change I think it's in one of the books maybe but personally I would get it done after the running in period. Just get it done locally with the right grade oil then stick to the normal service schedule after that with an oil change at least annually. It gets rid of any debris and running in swarf etc from the new engine.
Remember that engines with turbos rely on quality clean oil and also let the engine tick over for 30 seconds before switching off for cooling to prevent the hot oil carbonising in the turbo oil feeds.