The differences may be marginal but there is a general consensus that fuel from the major companies is of better quality than supermarket fuel. Higher octane fuels may bring a performance and economy benefit if your car is sufficiently modern, but the main reason for using a premium fuel is the additives which can help your engine's health.

Texaco do not give any specific information about the contents of its premium fuel other than to say it has 'a performance additive package', but given the small cost difference it may be worth using some or all of the time.