Which of the devices you listed are in the same marketplace as the DVIS?
Number 1: Cardiac imaging only
Number 2: Cardiac imaging only, no quantitative definition of "real-time"
Number 3: Cardiac imaging only, ultrasound technology
Number 4: Cardiac imaging only, appears to require the magnetic particle agent
So that's 4 cardiac only devices, none of which use wall power, none of which can fit through a standard doorway, and none of them with the breadth of functionality as the DVIS.
Seems like apples and oranges to me.