I have the gas Subaru-powered Powerstroke pressure washer from Costco. 3100psi @ 2.4 GPM = 7440 CU.
Just picked up an electric Powerstroke from Costco. 2200 PSI @ 1.2 GPM = 2640 CU.
Not quite sure what I think yet. Seems to take longer to clean the lawnmower decks, but it's a lot less hassle than the gas version and I don't wind up with as much water on me.