The BFD was with how the test was conducted. It's the consensus of most that not enough miles were driven to create a more accurate average over many tanks of fuel. Without the broader test sample there is just too much room for error.So I haven't had the time to read every comment here, but the OPs original post shows that the two tunes are within (less than) 2 tenths of a MPG. BFD!
So it comes down to which company you are more comfortable spending your money with.
It does often come down to which company you are more comfortable spending money with. I would hope that company has shown professionalism is in every aspect, from a transparent website to software engineering background to customer support and a solid customer base.