Once the software is paid for the cost of other conversions comes down to a small amount for the necessary chip... so it doesn't get much cheaper than this I think (my sons are itching to do the Delco thing with their cars too).
The main reason for Kalmaker/Delco apart from the above is to get access to the self-learning, 'gate control, water inj control and a bunch of other stuff including knock retard, etc,. What else can do this?
I did look into the Megasquirt and it is a close second but involves a lot of work for each car. Maybe if the Delco falls through I'll look deeper into MS.