We are, though we started out using EBS. As you mentioned, NVMe instance storage performs much better for our workload. We work around the lack of durability th

We are, though we started out using EBS. As you mentioned, NVMe instance storage performs much better for our workload. We work around the lack of durability through strong automation of point in time restore/swapping in of new nodes in case of hardware failures. And yes, reservations make a massive difference economically.