Bit late coming in on this one, but the biggest thing as to the success of any alarm system is installation. The deeper you can tie it into the loom and bury it in the dash, the harder it will be to bypass. A loud battery backed up siren in the dash is likely to help dissuade them too. Of course, jumpering a few wires will bypass the immobilisation on a carb and dizzy car anyway... It all depends on what you're looking to achieve. Putting the dizzy rotor in your pocket will stop anyone stealing it without towing it, and is free and easy. If you want the ability to track it, a hidden prepaid mobile with a permanent power supply and a tracking app is an effective and cost friendly option that's less likely to be disabled by a thief (as they don't know it's there, unlike an alarm system).
Just my thoughts anyway.
