The fact is that ethanol cannot absorb enough moisture from the atmosphere to cause a problem. It can cause a problem if the tanks have condsenation or water intrusion, but that is not ethanol's fault and can be equally problematic for non-E gasoline. The octane rating E10 will lose about 3pts over several months, but OPE is generally designed to run on 89, so if premium loses a few points it's not a big deal. Ethanol is harmful to oiler rubbers which were not designed to be tolerant, but for the last 10 years or so, OPE rubber has been manufactured with E in mind. If you keep it relatively fresh in a SEALED can (I stick with two months or less), use a good sythetic oil with a fuel stabilizer added, and know when to stop your saw when the chain gets dull, E is non-factor.
Now, don't get me started in the politics of E...I think it is a total farce and there are several valid reasons not to use E in fuel like the fact that is drives up food costs, drives down the MPG of vehicles, and keeps exploration and development of US's oil reserves in check . But to cry the sky is falling just because there is a little corn liquor in your saw's tank is just ludicrous.