Just to add to this. We were booked on Coastal for some flights in September 2018. Singita had booked us on them, but have now advised we swap to Auric, grumeti and precision instead.
we have taken their advice, as we have no way of knowing which are the best options....
Edit Having thought about it overnight, decided to swap some to Auric and leave one with Coastal. Two accidents so close together is worrying, on the other hand Coastal seems good and want to reclaim their reputation so should be safe.....As far as Singita goes it is my call.