Just a general question for those using E85 in the flex fuel Tahoe's, do you notice any difference in performance compared to regular gasoline? Also, this may be a dumb question but say you have a half tank of regular gas and add E85 to fill up the rest of the way. Would this hurt the vehicle at all or would there be any mixing issues? Just curious, I noticed they now have an E85 station not too far from where I will be working in a few weeks in Phoenix, was thinking about making the switch to save a little dough at the pump. Thanks much for your help. Matt.