"Many countries use PR without it leading to paralysis. The result is often coalitions, but that is not necessarily a bad thing."
I don't know. Coalitions might be nice from a democratic perspective, but they're fragile and they quite often skirt around fundamental issues.
Take Germany's coalition before the last election - because all sides were worried about the coalition falling apart, the major issues were avoided and put off until the next election. So they're not necessarily engines for consensus either. Now, I'm not saying govts need to be doing everything all the time, but I don't think that's healthy.
PR has other undemocratic features as well. If you vote for a party, they're almost certain to end up in coalition with other parties who you didn't vote for and who you might find very distasteful.
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I voted AV because I like the more nuanced level of expression it allows. When you're voting, you're essentially saying "Well, I'd like it to be this guy, but if it can't be him, I'd like it to be him. And if not him, then..." etc. I like the idea of being able to do that. It also has more emphasis on candidates than it does on parties - which I also like the idea of, and has interesting implications for UK democracy. PR systems emphasise parties just as much as FPTP does.