We have the Digital, first time using it on Fraser for a week, and not one problem, We use a gas bottle as we bought the hose, so can't help there, ( just get the hose to hook it to a gas bottle in case you run out on a little cylinder ) I have a 25lt flimsy bucket for the water pick up.
As for water consumption we have long showers ( easy when near a fresh water source ) we can have a shower out of about 15lt for the two of us a night.
Operation is simple plug it all in turn it on press start then turn the shower rose on and hot showers, very easy to use.
And a mate also has one has used it on several different trips and hasn't had a problem at all.
Red Dog