Good Question
I prefer food grade ethanol extractions. Not a fan of butane/propane and definitely a loud shouter of "no Isopropyl!" Water extractions wash out terpenes. CO2 is pretty decent.
I use the dry ice hash method without a screen, in a closed bucket instead of shaking it out. Once the cannabis is powdered I can use a 30 second ethanol wash and get a clean, full plant extraction. I end up using about 1/3rd the ethanol when I do this.
:D