I am going to echo mrkurt's sentiments on this one. The cost is really more about management and the ability to buy opportunity to scale without real friction,

I am going to echo mrkurt's sentiments on this one. The cost is really more about management and the ability to buy opportunity to scale without real friction, less about cost of backing services. In general thats what has made AWS so successful, and why PaaS is gaining in popularity. Granted its not always troublefree but for a large portion of the industry it alleviates a HUGE pain point which IMHO is worth its weight in gold. Ultimately, MongoHQ are pros and you're paying for their time and expertise, I am pretty sure if you were going to buy consulting time from them it would cost a lot more than what they charge for their service.