In case it helps Terraform users estimate their cloud costs, I updated https://www.infracost.io to support the new ms-based Lambda pricing (https://github.com/infracost/infracost/pull/248/files, it'll be in the next infracost release).

I'm interested to hear what people think about https://www.infracost.io/docs/usage_based_resources - longer term we could extend that to fetch average_request_duration from cloudwatch or datadog.