Looks like the folks at mongolabs like GCP:
"First, Google virtual machines (VMs) spin up really quickly. In some cases we have seen Google instances spin-up in 10 seconds, faster than we’ve seen on any of the other major cloud providers.
Second, Google’s network is incredibly fast, allowing for very low-latency connectivity between your Google-hosted application and your MongoLab database.
Third, Google’s live VM migrations make most VM maintenance completely unnoticeable to end-users. Google can transfer hot memory from one VM to another live, with minimal impact on VM performance. This means you will rarely see a VM reboot for maintenance. This makes our pagers happy. No other cloud can do this."http://blog.mongolab.com/2014/06/production-ready-mongodb-replica-sets-on-google-cloud-platform/