Out
The immigration argument is pathetic, there will till be immigration whether we are in or out, but if we are out there is a better chance of it being done in a way that is actually to this nation's benefit.
It's more a case of flexibility, we need to be independent to cope with the changing nature of the world, by aligning ourselves to a monolithic entity such as the EU we will not be able to react quickly to world events such as the migrant crisis which just shows how unworkable the EU is.
Alongside this there is also a point of principle, we voted into the European common market, a trade agreement, not into a political union. The argument of 'that was clearly where it was heading' holds no water to me, we did not vote for political union, we voted for trade. As such the disgusting practices of the EU during the roll out of the Lisbon treaty are an affront to our national sovereignty, identity and culture. The EU is an undemocratic sham and we must get out of it.