While there are a number of arguments and points being made by both the Yes and No sides I think the issue is actually very simple.
The FPTP system is undemocratic and produces an inaccurate result.
It works well in a two party scenario but we have not had that since the 1960s - over 40 years now.
We have LibDems but also important strands of political thought in UKIP and the Greens - and Nationalists in Scotland and Wales.
Only around a little over 60% voted Con or Lab last time!
A key argument for FPTP is it gives a clear result and as long as that is broadly in line with the vote that is pragmatic. Governments are scrutinised and accountable at elections every 4 or 5 years and at by-elections!
However, the results have for some time been too approximate or remote from the will of the people to be democratic. They are quite distorting and suppress new and important political movements coming through.
It seems to me the case for change is in fact overwhelming! Simply because both FPTP and the election results it gives are wrong!
The key reasons for no change are in fact inertia and conservatism.
AV is not the best solution but it is an improvement and all that can be agreed upon at this stage.
It is also a low risk change which will modify rather than radically change.
And that is why I will be voting Yes to AV!