Fed Up, I agree with you here. Having one's car broken into is almost as upsetting as having one's house broken into. I recently had the rear window of my estate car smashed and a case removed (which was covered by the luggage shelf). I hoped they enjoyed the three pairs of dirty underpants and socks which it contained. The cost was negligeable (apart from the case) but the inconvenience of getting crime numbers and having the glass replaced was particularly irritating.
Whilst removing a hand may be excessive, then at the time I must admit I entertained fantasies of hosrwhipping the culprit(s).
By the way, whilst your navigation equipment was stored out of sight, did you have any mounting kits in plain view? Thieves will often take the chance to break into cars on the assumption that the owners have done exactly what you did, and left the electronics in the car. It's safest to remove the whole mounting kit from sight completely.
My sympathies.
