I love the idea of the feature, and overall the implementation just works. I feel like there are some missed feature though. Namely notifications around received iMessages. If I am driving while the feature is turned on, and someone messages me, there is a reply to them letting them know I will get back to them soon. Unfortunately when I am no longer driving, I don’t get a notification about any messages received, so I don’t know to read my messages. A big pain really.
This has bitten me enough times to sour me on DND While Driving (at least until Apple fixes this).