Rinsing exhale counterlung is pretty easy, tip water in, drain through dump valve, repeat. Tip warm Virkon solution in, leave for 15 mins, drain through dump valve. Then repeat with water.
Inhale counterlung not so easy, no dump valve, water has to come out same way it went in. Is the only realistic way for doing this to dismantle the unit, take off the wing, lungs, etc.... ?
Maybe I confuse efficiency with laziness.