I want to go back to running 40:1 pre mix in all of my equipment. Just purchased a new ms462c and the numb nuts that got the saw ready put some kind of blue premix in it, it sure wasn't stihl ultra. I purchased a new 028av super in either 84 or 85 an have used 40:1 always. I am tired of throwing so many of those little plastic bottles away. I can't find anything near me but the little bottles of ultra. What is some good substitute oil that I can find in larger quantities and would be as good or better than stihl ultra? I use 93 octane from an ag supply that has its own dedicated pump. I have many other trimmers and blowers, clippers and pruners.