How secure are modern convertibles?

I may soon be moving back from law-abiding Singapore to the urban jungle of London. I love convertible motoring, having had an MG Midget in my younger days, but how resistant to break-ins or mere vandalism are the convertible roofs of modern cars? You could have cut the hood of my old Midget with a blunt table knife. Are modern fabric roofs any more impenetrable, or, to be realistic should I be considering a collapsible metal hard top? My main quibble with the latter option is restricted boot space and potential reliability issues.

Asked on 8 April 2012 by TA, Singapore

Answered by Honest John
They are not resistant to drug addicts or to vandals. A folding hardtop is more resistant, but a determined thief can get into any car. The folding roof of a Mazda MX5 Roadster Coupe takes no more boot-space than the folding soft-top of the soft-top version. It just adds a bit of weight and raises the centre of gravity very slightly. A nasty new trait comes from an EC ruling that all independent garages have to be able to access all fault codes, including locking codes. Thieves simply buy the code readers, break into cars, connect up to the OBDII port and drive them away.
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