Don't know at what level you are needing a security system but a relay and switch I can bypass in about 30 sec once acessing the ignition harness. Theres no alarm I can't or any decent car thief can't bypass (im not a car thief, I install the things lol).
The thing is delay-time equals getting caught...
You only need-digital tilt (for air jacks or towing), microwave (heat detect, internal only) lots of noise and lights and a pager alarm like DEI's Viper...
Things like black wiring etc is just a gimick. You rewire the ignition harness not the alarm. A fuel cut is easy to trace as well. Things like glass break are useless cutting the screen out can be done in a flash with the right tool.
A microwave sensor is unpassable. Once inside the car you can't hide your body heat.... Simple. But having it set for anything else e.g movement outside the car will just give a lot of false readings. Digital tilt for your wheels and towing (air jacks will not set off shock sensors they are for impacts only). Lights and sirens (I always put another back up battery siren behind the cluster as its hard to get to and rewire a car with it going off in your ear-any attention is unwanted attention by a thief. And last but most important a pager alarm that works at a great distance. So you can get there in time to bash him with your baseball bat.
As far as wiring goes any black or colour two or three point imobiliser is fine- But all this will do is create a time delay-hopefully with the noise he will get caught.
With the above system the car can still be stolen but it will;
1] sound off straight away
2] Give you time to get to it (pager)
3] Make the thief move on to an easier car
Hope this helps