Out, because the present system is unworkable operating as it does under disingenuous aims. The objective of ever closer union is at odds with a successful union, because there are 28 countries, each with their own agenda - so a politically unified Europe is not going to happen. It might just have been possible to have a single political unit at the outset with the 6 founding countries, but the time wasn't right. Now it certainly isn't.
This country joined a trading area, designed to ease the flow of goods and services. This is desirable.
What you have now is a group of countries with wildly different economies, but no political structure to ensure that problems are resolved. The poorer Euro countries are nowhere near the economic position of Germany, which in turn is able to sell its goods more easily than it should because the tail is wagging the dog, i.e. their trade should be based on a stronger Euro than it actually has to use. So the physical centre (a bonus in itself) and workhouse of Europe becomes stronger by the day as it is selling too cheaply due to the discontinuities of European economics to the detriment of the periphery.
Unless you can equalise the economies of Europe, the Eurozone is doomed to failure. It is doomed to failure because nobody is willing to cede absolute sovereignty to a group of unelected blokes (and women) in Brussels. The European Community (etc) has been going for over half a century, but nobody dare suggest political and economic union, which is the prerequisite for it to be successful. All have a misguided belief that we are better being closer together without crossing the drawbridge and willingly pulling it up behind themselves.
Basically, I think a unified Europe is probably the right tool for the job if they wish to have a greater voice as an economic force, but the operators are incapable of using it correctly. Therefore, it is better for all if it were to return to the trading area we all joined 40+ years ago. Whether Europe allows that is a different matter, but a reduction in the power of Brussels would benefit most people in the EU, profligate spending being the order of the day. It is too unwieldy to be efficient, or accountable.
This country can stand on its own two feet just as most others could too if they chose. What would be required however, is a change in the mindset of people from today's dependency culture to one of can and must do, which is a moral compass issue at the end of the day.