Founder here - the "up to 3x cheaper than Heroku" depends on the exact compute profile, but as a point of reference, Heroku pricing starts at $250/mo for a single 2.5 GB RAM instance on their Performance tier (https://www.heroku.com/dynos). Generously assuming that you get 2 dedicated vCPU cores, the equivalent Porter cost is ~3-4x cheaper

Edit: Porter Cloud also supports Postgres and our in-your-own-cloud offering just uses RDS under the hood for AWS