Founder here.

1. when we'll charge a credit card (which should happen in the coming weeks as we're incorporating the company), we'll be already cheaper than Heroku in a price/performance ratio 2. to be honest we're more pessimistic than you about the number of containers that we can host on a single server like the one you cited (at Appsdeck we use only SSD equipped servers with more cores than in the machine you cited)

That said, our price could change a little bit depending on the real workload that our cluster can handle in real life.