I don't really think there's anything wrong with E10 in vehicles manufactured adter 2001 or whenever they began making provisions to fuel system materials, or really any vehicle which isn't using a fixed fuel delivery system, ie carburetor. So, I wouldn't skimp on the extra octane for the SHO.
There are probably some differences in the basestocks between the oxygenated and unoxygenated gasolines available in your area. Most notably, the 89 basestock is 89 PON, right out of the storage tank. Any fuel blended with ethanol is refined to a lower octane, and then relies on the octane benefits of ethanol to bump the AKI to meet the 93, 87, 89, etc PON seen at the pump.
Also, regarding the development of cellulosic biofuel, I believe that was always apart of some of the mandates found in the Renewable Fuel Standard. As the volumes of renewables were forced to grow every year by mandate, the RFS sought to reduce the burdon on the food supply, and sought to encourage the development of cellulosic ethanol. But the EPA keeps delaying deadlines and reducing volumes, becasue they are unfeasible. And the ethanol politics have cooled down in recent years and nobody is buying it anymore. And lawmakers are attempt to repeal and all of this...It's yet another circus.
