The start/stop system on my 2016 car was so slow to restart the engine that I habitually turned it off. Since getting my new car I have continued to turn it off until today, when I discovered that it is now usefully improved. The car starts rapidly enough not to be embarrassing, so I will continue to use it, in the interest of the environment, especially in our urban streets.
However, the start/stop only operates when the car is happy that it should - the battery has enough charge, the cabin does not need heating or cooling etc. Some city councils have recently declared that they will be fining drivers who do not turn their engine off in congestion zones, so do start/stop systems have a problem here? I’m guessing that those with start/stop systems will be expected to manually override it in these situations, or risk a fine.