I encouraged my old fella to get one fitted when my stepmum died and the rest of the family left home, it saved him loads, round here you can have one on a trial basis.Apparently they'll fit one and you try it for a year, if you don't save money they'll take it back out.
Interestingly enough I see they stopped fitting the meters with the repeater box on them, a few years back, the meter was down the hole and they fitted a secondary display at the house, usually in one of the other meter boxes. this meter was connected to the main unit by a thin 2 core cable, obviously the main meter generated some kind of voltage to cause the digits on the second meter to move.
I always thought that if you applied a small voltage to that cable, then it would stop the main meter from reading, it must have worked, because all of a sudden they started using meters that were mechanical only.
Interestingly enough all this talk about smart meters and saving money is all BS! it's all about revenue protection, a modern electric smart meter can detect a power loss, and inform the meter company, if there hasn't been a power outage in the area then they know someone's been at it! The modern gas meter is the same, try and move it and it goes into lockout, so you can't reverse it, or swap it for another one.
I know one guy who was always fiddling his meter, I think they had an idea, but couldn't catch him at it, anyway they fitted these new meters and as soon as the fitter went out of the door he was at it trying to fiddle the gas! It went into lockout and he had to get them back to reset it, he tried saying it never worked after the guy fitted it, they knew otherwise. Anyway he was given a warning to leave it alone in future.