Today under the "proposed" (but I believe not yet implemented) bandwidth overage model, if a $5 droplet doubles its bandwidth usage, it will incur an extra $20 cost. This causes headaches for developers who have to think "OK do I need to purchase 2 droplets to spread the cost out" etc. It would be super convenient if bandwidth overage costs equalled the sum cost of the initial droplet, so if you double the allocated bandwidth for a $5 droplet, it costs you an additional $5. It would simplify not having to worry about "am I about to go over and go into expensive bandwidth range?" type fears.