My average bill has gone down somewhat. My gas meter got a new smart meter module, and it was replaced twice in the first six months. The electric one has only been replaced once, and I suspect it was due to our deliberate reduction in energy use.
It was funny. The gas meter has a "unit" indicator that is visibly rotating when gas is in use (water heater and central heating) and it was not rotating at all at first. You'd think something that simple would be checked by the installer.