The standard immobiliser is Thatcham II and is decent, particularly with old fashioned keys. A bit more vulnerable with keyless systems (are the higher spec versions keyless?), but if the keys are suitably secure and shielded then the only way past it is key cloning - this isn't impossible but is difficult, and its unknown for dodgy dealer employees to sell the required code info on the dark Web or to take backhanders for accessing the info.
Forget Faraday pouches - been to too many jobs where the keys were one and the vehicle still vanished. Good solid biscuit or tobacco tin at the very least.
The Blackjax has true anti-hijwck, so even if they threaten the code out of you they'll only get half a mile down the road before it gradually shuts the vehicle down. Unless it's been updated since I retired in 2020 the Ghost doesn't, so is only as secure as the size of your balls if you're being held at knife point for it.