AV would have given Liberal Democrats 32 more seats in 2010 general election.

The Guardian reports that he Liberal Democrats  would have had greater freedom to choose whether to form a majority coalition with either the Conservatives or Labour if the last election had been held under the alternative vote system, according to research conducted for the University of Essex.  The British Election study, supervised by Professor David Sanders, concludes that the Liberal Democrats would have gained 32 more seats under an AV system – largely at the expense of Labour.