Excellent overview of these similar but different applications. A observation I will make -- hopefully merited -- is that Scrintal seems more focused on its purpose, while Heptabase seems to have a more "throw everything into the pot and hope for a tasty stew" approach. The developers of Scrintal seem more disciplined in their vision. That's not a knock on Heptabase. It has far more features than Scrintal (even simple, but powerful things such as the ability to label the visual links on the map). It is going to be interesting to see how these two applications evolve, and what impact they will have on the rest of the PKM world.