Having just spent nearly �1,000 after some toe-rag smashed my car window, scratching paint, levering with tools, wrecking facsia, and eventually only hoofing it with the front panel, I should think that anything that deters the litle s*ds is a good thing.
I thought that coded radios are a good thing as the tykes that thieve the radios only get �30 or so for them if they're lucky (whereas to buy new could be hundred or more) and they are not going to dilute their profit getting the code thing sorted. My previous car had no less a tasty radio, but was coded and a small sticker to that effect on the window and it was never touched in nearly eight years.