Had the honor of being the first person (other than the designer/engineer Kevin Gurr) to dive the Hollis Explorer Rebreather. What a game changer! Incredible and surpassed my expectations!!
It is an SCR but it sure does not feel like it. One gas. Tiny. Lightweight. Has gaseous CO2 monitoring and temp profiling of the sorb. Trims beautifully. I think I used around 10-15 psi per minute (from a minuscule tank) and it held set point beautifully, adding gas as needed with barely a trace of bubbles. I can't get over it! Great machine.