I find the speed recognition too poor to be useful, so I turn it off every journey, the flashing is quite distracting. Even Google Maps, which I use for navigation, often gets the speed limits wrong. I have heard talk that a future "safety" rule for new cars soon may be to default to speed limiter on, using recognition. I think this is inappropriate, not just because the current technology can't get the recognition right, not just because speed limits can depend on the vehicle's state (eg lower for towing some loads), but mainly because a good driver should pay attention to and observe the speed limits and having the car do it - like so many of these features - will both deskill and lead to distracted driving.