One of the large security companies I think it is securicor uses VHF tracking - this is because is very hard to stop. Realistically if some one is very determined they will get your car. Thieves have been known to point a gun at you, your child or your partner and who wouldn’t hand over the keys and tell them how to start it.
But if I can all make it as hard as possible for thieving scum to take my pride and joy I will and do so. Layer the security if possible so they have to get round multiple security devices to take it.