Looking for thoughts on the following...

My Viento build currently has a matched BMW ECU, built-in immobiliser, chip reader and chip key. I also have a spare ECU that does not have the matching immobiliser. Basically, I'm going to get one of the ECU's reprogrammed to delete the need for the BMW traction control speed signal (which I don't have) and to get a better map for the nature of the car.

My choice is to have the one with the immobiliser re-programmed and to keep the immobiliser system intact or to have the spare ECU reprogrammed and the need for the immobiliser signal deleted at the same time. BMW ECU's and matched immobilisers and keys go on e-bay for £50-£100 so the obvious choice would be to have the spare done and to sell the immobiliser one to release funds for other bits of the car.

The reason for posting under "insurance" is that I was wondering whether selling the immobiliser would be a false economy because my insurance premiums would be reduced if I keep it.

I doubt your insurer will recognise the immobilizer with out paperwork from an installer. But great for piece of mind as they are often harder to get around than aftermarket systems.

I agree, I dont think that insurance companies take much notice even with a certificate.

In my mind I would be thinking that as long as they don't have my keys when they rob my car then it won't be banging off the rev limiter thanks to some thieving bastards.

They didnt even ask me if i had one or not. Doubt it would of made much difference.