Good idea.
I may end up doing that with the ion. The problem with the Etha is that it requires a solenoid housing (not sure if you're familiar with the marker or not) which basically dictates solenoid placement/type. I suppose if I wanted I could tap the body for barbs and move the solenoid. The roughly 300 psi operating pressure makes it a bit tough to find a solenoid that can handle that sort of pressure although I could probably use one rated for lower pressures and hope for the best.