I have no intention of letting one of these meters in to my house. However, I though you might be interested to hear of the experience of a work colleague who is the treasurer for a Church. They were required by their electricity supplier to have a smart meter fitted. After a few months they received their first bill. My colleague was looking forward to it because, as he reasoned, it would be accurate and he would only be paying for the electricity that they had used. When he saw the bill he was so confused he had to ring the company for an explanation. The bill consisted of a reading taken during the final month, on the fourteenth, if I remember correctly. The next line was an estimate of the electricity used from the fourteenth to the end of the month. The company explained that the premises were on the schedule to have the meter read on the fourteenth of the month and that, as a consequence, the remainder of the bill would be estimated based upon the previous years usage. You will not be surprised to learn that the customer service representative was only able to reiterate the same explanation when asked why the meter was not read at the end of the month. My colleague, as you can imagine, is not terribly impressed.
I am entirely serious about the accusation of speculative billing. British Gas used databases to identify and mis-sell heating "free safety checks and upgrades" targeted at pensioners - the more elderly the better and IIRC they got a fine (which went on our bills no doubt)
The speculative billing model was intensively refined by the phone companies in the 90's - I worked for a company back then manufacturing call logging equipment and it wasn't unusual for BT to try and scam a big customer for 25% extra on their bill... When presented with unequivocal evidence of their "administrative error" no communication was entered into but the disputed amount simply disappeared off the next bill.
The intransigence can be amazing - one acquaintance has paid for electricity logged (and emailed to the supplier) meter readings but the company is insisting he pays the estimated bill...... this has been going on for over a year with threats aplenty from the billing department.