We had them installed by First Utility two weeks ago. Both meter screens have been completely blank ever since and the monitor provided shows that our next estimated bills will both be £0.
FU (yes, I now see the joke) aren't at all interested apart from claiming that the smart meters can take up to 28 days to connect. The engineer fitting the things, on the other hand, said (after the work was done ) that the signal was very weak in our cellar but they made the decision to go ahead anyway and might well have to come out again to put the standard meters back.
So we now have no idea at all what these meters are registering, and are looking at yet another day of being stuck at home while new meters are installed (the work took five hours).
And having looked at the monitor, all it will do if it does miraculously start working is show us how much energy we are using at a particular time, which doesn't seem particularly useful or high tech.
From our experience, I'd say if it ain't broke, don't let them fix it.