All the C150/152's that the door has popped open on me have had twisted airframes due to years of abuse in flying schools.
I used to brief students on the tendency of doors to pop open and also what they should do if it happened on the takeoff roll.
Although proberly not suitable in the UK due to the climate, about the only time C150's are none smelly and quite pleasant is when the doors are taken off. FAA land thats a couple of pins and very little paper work in the UK I presume it would be a complete pain in the backside.