We're about the same age and I too have no convictions. I live in a suburb
of Glasgow where car crime is generally pretty low (though my next door
neighbour had the soft top of his Honda S2000 slashed the other night). I
work in risk management in the insurance business (though nothing to do with
cars unfortunately!), so I understand how underwriters assess their risk.
Where you live has a big effect on premiums (it can sometimes vary from
street to street and even what side of the street you are on), particularly
if the car is not garaged.

Bob H