A recent article said that the so called smart meters can overread by 600 percent if you have low energy bulbs, as the way they handle the electriciy affects the meter. Some estimates give the cost for the meter as about £300, but I don't know if it's done on an increase in the stabding charge, or on the unit price, which means low users will pay less for their smart meter, than higher usage users will.
There has been reports of faulty smart meters switching the power of (this feature allows them to do it remotely if you are in arrrears) so this alone proves that it's for the suppliers benefits, not yours. Untill thet start supplying clamps that you can put your equipment, that will link into your phone/computer, and actually show what each item is consuming, and over what period, then smart meters are just a waster of time for consumers. I give it 3 years before everyone with a smart meter gets put on a variable tarrif that whilst promising to reduce your costs, will actually cost you more.