Hi BritBrit
To me there are two key issues in the referendum. One is the economy, and there is no doubt that the risk to the economy is greater if we leave. That is not to say the economy could not ultimately be stronger if we left, but that it is disingenuous to suggest that the risks are not greater.
The other issue is immigration and it is clear that leaving would provide us with the opportunity to control immigration to a far greater extent. However, it does not mean we will be able to realise that opportunity. So for example, we can already 'control' non-EU immigration yet spectacularly "fail" (failure only in terms that the Government's aim was to reduce it). Current immigration rates are 277,000 non-EU and 270,000 EU. We already have a Points Based System for non-EU nationals. We are to my knowledge the only country to try and use a PBS to reduce rather than increase immigration - and it has clearly failed. The leave campaign hold up the Australian system as the ideal but don't appear to understand that PBS has very little to do with their control of their borders. The PBS is aimed at individuals who wish to migrate and have no job. Any employer can, outside of the PBS, permanently or temporarily sponsor someone for their visa. Thus overall, the PBS accounts for 15% of all migrants entering Australia, and only 38% of those given permanent status. Australia have a big problem with overstayers as so many come on temporary work visas (mainly Brits, but of course we don't like acknowledging that we may be unwanted).
The reason Australia have total control of their borders is that ANYONE who is not an Australian must have a visa to enter the country. NZ citizens can apply on arrival but everyone must apply in advance. Now if the British Government want to go down that route that would enable control of our borders - but that is NOT what the leave campaign have stated would happen. And we would have to understand that if we did that, then it is most likely that all other countries would impose the same restrictions on us.
Which brings me onto the issue of British movements.
In addition to the non-EU and EU figures stated above, there were 87,000 British "immigrants" (I think many people don't understand that the net immigration figure of 330,00- includes leaving and returning British citizens - so in the early years of an exit, we may well not be able to keep immigration in the promised "tens of thousands" unless we deny entry to our own citizens).
So, whilst immigration is not the most important issue to me, I think it really important for those to whom it is the biggest issue to understand that immigration is a complex issue and there is absolutely no guarantee that leaving will enable it to be reduced. And I haven't even touched on the fact that entry to the single market - if we decide we want to retain it - will almost certainly demand continued free movement of EU nationals.
This is an interesting paper on the Australian system and its suitability to the UK. I should point out that Migration Watch are an anti-immigration think tank - so this is not the Remain Camp trying to 'poo-poo" the Leave Campaign's claims.