The CloudHealth Platform utilizes the Unblended/Direct Cost.
That displays actual cost by showing the actual usage per instance type_per account, the actual hourly price of those instance types, and also the actual discounts attained from reservations per account. Unblended cost is more accurate, it allows for better decision making because it displays actual cost/usage per account and it factors in the impact of Reserved Instances per account.
Below illustrates how blended and unblended costs may manifest in cost reporting:
CloudHealth recommends always viewing costs as "unblended" to get the most accurate view of your costs.