muvment

And what other options do i have for an aftermarket theft (and break-in) deterant?

Geo

i installed one on my GTI, not my A4. so, this technique is not applicable, though you could adapt.....
i interrupted the coil wire and ran it to a switch inside the car.
i used a black slide switch (hard to see in the dark) and mounted it at the bottom of the plastic surround of the gearshift. UP (same as pulling the e-brake UP when i left the car) made the car impossible to start. DOWN, as in releasing the e-brake, activated the coil.
all radio shack stuff.
i haven't studied the schematics, but i'm sure there's a fairly simple (low-voltage) way to do the same thing on your car. just hide the switch.