I remember reading in the papers once than one lender found that interest only mortgages between 2004-2007 were 6 times more likely to end up in arrears than mortgage and interest mortgages. Not sure if that applied to all the banks or not. It would probably depend on the proportion of investment property versus pdh too. It would be interesting if someone had a source - surely someone should have worked it out by now, as part of some academic project if nothing else? I suppose the banks have learned to stop offering 100% interest only loans and consumers have learned to stop buying them.