It is good that you are considering running on premium fuel as it does have a better calorific value that the E10 fuel which containing 10% Ethanol offers less performance per mile than a better quality higher octane rated fuel.
Since running my older car (but not bikes) on E5 it makes a huge difference on performance and MPG.
Not entirely sure what difference you will notice on a newer model like the Grandland but only one way to find out.
When it comes to Shell and Esso I imagine they would be of similar quality but again its worth trialling each one to see the outcome