How do factory security systems compare with aftermarket systems?
It depends on several factors, and you should try to compare apples with apples. For instance, most factory “security systems” are actually “antitheft systems,” meaning that they are essentially engine disable/starter kills and not full featured security systems with a sensor. But say that you are comparing true security systems. If they are both quality systems, carefully installed, then the main factor that weighs against factory security is the assembly line: all systems for a particular make and model year will be installed exactly the same, with publicly-available instructions in the service manuals telling thieves how to disable them! Also, many factory security systems lack a shock or impact sensor and rely on door triggers.
