Marvintpa

The "in the background" calibration of the cells in air seems to be different.
Inhale counterlung "on the side" of the breathing path.
Efficiency increase for an axial scrubber.
Building the ADV and solenoid shutoffs into the over-the-shoulder mounted off-board gas injection blocks is something that also appears a little different.
Having three levels of the same rebreather designed for difference types of diving.

None of these is likely earth shattering but put them all into the same package with a hopefully solid design and it might just be a good rebreather.