AMS? Do you mean a proportion of seats appointed through PR? I have to say that I’m not personally in favour of PR, for a number of reasons - but there’s no doubt that where results are marginal, as they usually are in UK-wide elections, it would change the nature of politics completely. As it happens, in Wales so far, as it’s predominantly Labour, with PR accounting for 8 Tory and 8 Plaid seats out of the 20 PR seats, it’s given Plaid a voice on coalition governments, but hasn’t benefitted the Tories who are the second biggest party with the 8 regional 8 constituency seats out of 60.