Thanks Jeff, I expect you're right.
I may well have previously clicked that menu item with 2003 set.
When I selected it I was expecting to see the preset dialog where you could choose the settings and which bits to apply, but instead it just overwrites with your current settings.
At any rate I have now done two things, set the default settings, and also created a new preset "General - Zeroed 2010" which I have set as the one to be applied on import. And that setting seems sticky so it should be sorted now.
Thanks for the help.