I also use 3 airless rigs. One for drywall spray outs and exteriors(all latex), One for enameling trim, doors, ect.(only oil), and one for clear coats(usually lacquer or conversion varnish). For the trim and clear coats i use the 440i.
And for the drywall spray outs/exteriors I have a gas powered speedflow the has two 150 foot lines. I leave this pump in the box truck so I don't have to carry 100 gallons of paint into a house to spray walls and ceilings. I so nice not hearing the pump while doing a spray out.