I've been using Amsoil synthetic 2 cycle oil in everything I've owned with a 2 cycle engine (even outboard boat motors) at 100:1 for 27 years. Never had to change a spark plug, clean carbon out of the exhaust and have never had any engine lubrication problems. It's much more expensive but well worth it. I bought my first chain saw 27 years ago and it still runs good but I don't use it much because I bought some other chainsaws with more power. I use regular 2 cycle oil for break in only.
