OK.
Healthy discussion with some disagreement.
I'm going for the bulb between D and coil solution. It's easy, cheap and I don't like flashing warning lights on a Vin. But thanks for all the feedback, I may look at the alternatives later.
Tom
It sounds like you have similar thought to me. I put an LED on my Fireblade to look like an alarm. I put a cutout switch in the toolbox that also switched on the LED. Poor man's immobiliser - you see now why I like the cheap option.
H