Obviously these mortgages aren't really as available now as they were a year or so ago.
But earlier I caught the end of a discussion about Northern Rock and how people didn't consider the reality that when they take out a 125% mortgage they are already in negative equity as soon as they move in.
I can kind of see why someone might take out 100% although even that would be risky IMO, but 125%? why why why? Surely if you had that much debt that you needed an extra 25% of the value of your new home to cover it then that's not really the best time to be considering buying a house in the first place?