Stihl Ultra Syn is available at all Stihl dealers. The company holds close on their products so you don't see it at the box stores. This is the only oil I use and I do use non-ethonol high octane because it is available here and all my two strokes do well on it.
That includes several large chainsaws that cost much more than my model engines and they are worked hard at times. I have so far had no problems and plan on continuing with this mix.
