It seems that several people here are missing the point rgaeding why you need to purge a two stroke running alcohol (E85, M85, or whatever) for a fuel in the first place. If the aluminum parts in your engine corrode, who cares. What you are really trying to protect are your bearings.
Conversely, the reason you do not have to purge a four stroke engin on this tipe of fuel is that the lubrication comes from somewhere bedised the fuel. However, you get to change your oil more often as alcohol dillutes the oil and washes down your bores. :geek: