Whether by AV or anything else, no elected MP's (mis)behaviour with expenses will change.
I had many reservations about AV ages ago, but what finally pushed me was John Reid of all people (Cameron's unlikely ally in the NO camp) - he expressed so clearly and articulately the seriously anti-democratic problem of totally destroying the ancient basic principle of "One man - one vote" (which in the last century became "One person - one vote"). My democratic right is exactly equal to yours - to demand that MY vote is counted only ONCE in favour of my chosen candidate, not repeatedly used for the potential benefit of the candidates that I DON'T want!
This AV: "One person - a variable number out of several votes" is unfair, unbalanced and (have we all forgotten this?) NOT REPRESENTATIVE OF THE VOTERS' WISHES.
Only three countries use it, one of which now wants to get rid of it.
As Dirty Harry said, "I hate the system and will always criticise it - but until someone comes along with a better one that makes more sense, I'll work within the current one." For all its stupidities and weaknesses, the creaky, current so-called "first past the post" method is far more preferable to the nonsense of AV.
However, my big question is this, given the whinings over the last half century by Lib Dems, SDLP (anyone remember them?) and Liberals before them - WHATEVER HAPPENED TO THEIR PRESSING DESIRES FOR PR? This works already in Northern Ireland, the Scottish and Welsh Assemblies and half of the world's democracies, including most "member states" (formerly countries) of the EU. Why has nobody mentioned PR at all during this important debate? Are we being fooled by a conspiracy that only two systems exist - the current one and AV?
If any one of you doesn't know what PR is, then I will believe that the above conspiracy did exist - and has succeeded.