I have been spraying Benjamin Moore's Impervo. It is a water borne acrylic. After a lot of testing I can now get a very acceptable finish. The equipment I have is a 4 stage Fuji with a gravity feed gun. ( Don't let the gravity feed notation fool you. There is a tube that comes from the turbine and into the top of the cup to pressurize it.) A nice feature of the gun is that the cup can rotate relative to the gun, so when the gun points straight down, the cup can be positioned straight up.
In any case, I have found that adding 10% water and a bit of extender makes a world of difference in the finished product. I have also found that adding too much water sprays well but causes the "satin finish" to be flat and chalky looking. Too much water can destroy the final finish!
My $.02
Len