They can easily get in, but once you lock the car, and roll down your window. Try opening the door by the handle, you'll see what happens, lol.

Even if they manage to get inside there's nothing they can do to start the car without the RF signal key. And the radio is worthless to install in any other car, due to the fact that the radio reads the vin code to make sure it's in it's correct place.

So there's really nothing they can do to your car unless they just want to slash your leather seats or steal parts off it.