I believe that you should leave the door locked simply because many people who would consider stealing something won't go to extreme measures, I know a guy who got his ipod stolen because his windows were down, probably would have never happened if they were rolled up, simply because it takes to much effort, kind of like cutting through a convertible top. Of course, this won't detur everyone, but it will stop your "casual" theives

They cut about a 3 foot opening and stood on the hood and i guess went head first in to grab the sirius radio and then cut the wires when all they had to do was unplug it. I hate them.

But never, ever, ever leave anything in view.....

Matt

I owned a Z3 roadster for nine years, and never once was it 'molested'. When the top was up, I always had the windows rolled up and the doors locked. The reason for this is that BMW doors, when electronically locked, will not open from inside. So, you can cut my top, and smash my windows, but you still won't be able to open the doors! I think MINIs do the same thing now. In areas where I was really worried about security, I threw a car cover over the car and locked it with a tether, crooks tend to pass by that which they do not see. Good luck, and always park in well-lighted, safe neighborhoods. Here in DC, if I need to go somewhere late, or to a bad neighborhood, I take a taxi or metro.