It's hard being grown-up about politics, I find. I've no truck with UKIP's policies, but under first past the post (FFTP) the relationship between votes cast and seats won for UKIP and the Greens is so much larger than for Labour and Conservative that it's easy to see why so many people, and not just UKIPpers, are saying FPTP is no longer a fair system.
It seems that some form of PR would have reduced the SNP landslide somewhat, brought about another Tory-led coalition, saved some LibDem seats and made UKIP a force to be reckoned with.
It's been said for a long time that FPTP leads to more stability and consistency, whereas PR almost inevitably leads to coalitions, which some see as more unstable At this point in the discussion someone usually drags in Italy and jeers at their frequent succession of coalitions, but that overlooks stable and economically successful countries such as Holland.
No electoral system is completely fair, perhaps, but a system which alienates large numbers of voters and results in destructive frustrations must surely be called into question. Democracy only works if people believe in it.
We can hardly expect Labour Conservatives and SNP to be keen on changing the system for Westminster, it would greatly reduce their potential for large majorities and significant power blocks.
PR systems look, to many of us, off-puttingly complex to understand, whereas FPTP is at least simple.