I didn't know there was one ... (where is it?)
I just noticed this week (after more than a year) the small LED on the dash, I assume for immobiliser? I'm guessing mine doesn't light up or I'd have noticed it before.
I only had one snag so far, which I noticed at purchase but left so far as it amused me - the rear fog and reversing light are in the LHD positions, on my RHD car. I might have them swapped at the next service now that the novelty has worn off ...