I prefer to pay DD, si, but I have been screwed so many times by companies faffing me about (all their fault not mine, and cost me a fortune in 0870 phone calls). So we have a prepay meter with a key, and it's reasonable. As we have gas heating and boiler, we don't use so much, but we used to have really inefficient electric heaters in our old flat that just ate electric right up!
They aren't that bad, they don't just drop from �1 to nothing, leaving you in the dark!
I would advise, if you're getting a key meter, to ALWAYS keep receipts. And take frequent meter readings (as you would with a credit meter anyway) so they can't try and rob you.
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