More than one machine is definitely great in case one breaks down. Wouldn't be easy, but at least doable.
Theron, have you heard about the new Airablo machine Leader is marketing? Extra membrane with it's own pressure pump, working in series with an existing RO. It sounds pretty sweet to me, but is still quite a chunk of change! I need to get the 600 I have back up to speed before next season.
Willow Creek Farm
2200 on vacuum, 3hp 3ph Busch pump
30X8 Leader oil-fired evap. w/ steamaway
Airablo 600 RO