I'm in favour of PR too. There is no good reason why Westminster & England's councils shouldn't use it, except for the vested interests of MPs and councillors. As already said, it's not as if any of the new devolved governments set up use FPTP - Scottish parliament, Welsh Assembly, London thingy-whatsit, and I believe Scottish councils are going to be using STV (if they haven't already adopted it - I'm not sure.)
I think the fact that no new institution has been set up with FPTP is proof that no politician takes FPTP seriously as a way of electing democratic representatives. After all, it's just a hangover from the days when political parties weren't the organised forces they are now.
And another thing, although no-one seriously expects politics to become all sweetness & light just because of the adoption of PR, I do believe politics in this country would change significantly. For example, I think it would have been much more difficult, if at all possible, for Britain to have followed the US into Iraq. Incidentally, the US is another place that could do with a serious dose of PR, but that's another matter.
Rant over
