Transponder immobilsers are very difficult to defeat, especially when they're integrated with the
. As I understand it, the crooks options are:
1) Steal the keys
2) Lift/tow the car
3) Come equipped with a pre-paired
and key, and fit them to the car on the spot.
For most thieves, only the first option is really practical these days. The technique of 'hooking' was born from this, and is the reason why you should never leave your keys in line of sight of your letterbox.
If it's a particularly desirable car, then it's not beyond the realms of possibility for them to break into your house just for the car keys. In some cases, they've been known to hold the occupants of a house hostage and demand the keys under threat of violence. We're generally talking 40,000 quid plus cars here before this happens though, so most of us Renault owners have little to worry about there.
Most of the old school 'joy rider' types (how I hate that term) just look for older cars that were made before the immobilisers became standard. As there aren't so many around to pick and choose from, your chances of having such a car stolen are probably greater than ever. So if your neighbour has an H reg Cavalier (by way of an example) the crooks will have a bash at that and leave your Laguna alone.
That's not to say they won't break in and steal your CD collection though. That's just as likely as it ever was.