RBS have/had a similar scheme... I don't know if you have to have some kind of Premium/Advantage/Plus/Extra/Gold account to get it, but AFAIK you didn't have to pay extra for it on top of the cost of the account.
Theo
When we had our (3) doors upgraded, the extra cost of having "keyed alike" was zero, but the installer commented that they had never been asked for this before.
Robert
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