How bad is 89? (For MS3) (I know the website says 91)
Obviously 87 is no good...
Uh-oh... Well, please read my post below where I ran two full tanks of 89 through my MS3. After you read it, decide for yourself. As you will see, the discussion got pretty "lively" at times.
http://www.mazdas247.com/forum/showthread.php?t=123714495