Every lawn care, chain saw and small engine forum that I found had folks that rave about Opti-2 for two-cycle engines. They run it in their mowers, weed eaters, chain saws and blowers with many of them using it in multiple engines for many years. The only negative comment I found was from a guy who said it fouled his plug.
Like here at this forum, there are people there that are worried about the 100:1 mix, but nobody that actually uses it said they had a problem.
I think this link states it best-
Which 2-cycle oil for Toro snow blower.
If the people that depend on these engines for their livelihoods trust it, thatís good enough for me. Iím switching.