Eurozone
Britain is a country known to adhere to special rules, regulations, and principles, to be neutral, conservative, and probably to be unique amongst other advanced countries in the world. The official reasons for staying out of the Eurozone are a good example of what Britain stands for.
In the first place, Britain should know best: united we stand, divided we fall. There is no way the economy will be successful with a single currency within the Euro currency zones.