Thankfully, I live in the "safest city in America", so I don't have to worry about that :wink:
My 85 442 has only been a daily driver for one of its 20+ years in existence. In that year I had to leave it in a public parking lot way in the back (so it got no dings). Never though about it getting stolen at the time.
Seriously, though,I do think that were you live slightly has something to do with how safe these cars are. For example, I believe they are really coveted in Florida and also the Chicago area. Areas along the Jersey Turnpike from Philly to NYC also see these cars get stolen often.
My insurance does stipulate that this car now be kept in a locked garage when not in use. I believe that help your odds of not getting stolen considerably. Someone also told me not to get personal plates-it is easier to remember them and look them up. also, after car shows, make sure nobody is following you home.