I can't really see the point of AV - if no candidate gets more than 50% of people's first choice, then whoever wins will still be the first choice of less than half the constituency. Seems to me it's wanting to have your cake and eat it, to vote for who you want and then to say, oh, no, I didn't really mean that, let me have it again. Doesn't work in chess, counts as cabbaging in rounders ... ;)