Yes, you only get the (small) insurance discount if you have a maintenance contract which costs more than the discount, AND if you fail to set the alarm when you're out, your insurance is void.
However, if you have an alarm and don't request/get the discount/inform the insurer then you don't *have* to pay the maintenance contract, and if you fail to set the alarm, your insurance is still valid. Only problem? You don't get the (small) discount on your premiums.
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