One trick to watch out for: a cloud provider offering inexpensive egress can still make high-egress expensive by controlling the network speed of their instances. Several vendors require you to scale your whole instance if you saturate any of the components (like needing to upgrade from the 2 CPU to the 4 CPU instance to increase the network throughput, even though you don't need more CPU). On paper egress looks cheap and the instances look well priced for the hardware you get, but if you workload doesn't need balanced a balanced instance (1 CPU / 1 GB RAM / etc.) the pricing can get wonky.