the vast majority of car thieves are going to be brain dead junkies looking for a joy ride. An immobiliser with 3 points of immobilisation is going to stop every single one of these from taking your car. A proffessional on the other hand...Well I dont know about gone in 60 seconds but yeah I agree your car is going to go, its just a matter of taking a bit more time. Also even though the siren may get ripped out in 10 seconds, if your car is parked across the street or outside your window then this is long enough.