Who told you E10 is a mix of 95? E10 has a minimum rating of 91RON, but can be 93-94 (Mobil/7 Eleven advertise as 94RON), it doesn't go to 95RON. Although, I'm sure you can run it on E10 91RON, it'll retard the timing heaps. Who knows what it'll do to your fuel system. If you want to use your fuel card, buy something that is designed to run on E10.