I'd use truefuel or the stihl equivalent in your shoes. I can totally recognise the situation when some old fuel sits in the trimmer and the can over winter. That's when stabel fuel shines.
If you like to use pump gas anyways, I have had some success using stabilizers in like boat tanks that does not easily empty in fall. Suppose it would also work in the garden, however it is not free either and it is another thing to remember. So, naaah, if using less than a gallon I would buy stable bottled fuel but pick the cheapest. I suppose Stihl is cheaper than the other just because of the extreme packaging of trufuel...
If you like to use pump gas anyways, I have had some success using stabilizers in like boat tanks that does not easily empty in fall. Suppose it would also work in the garden, however it is not free either and it is another thing to remember. So, naaah, if using less than a gallon I would buy stable bottled fuel but pick the cheapest. I suppose Stihl is cheaper than the other just because of the extreme packaging of trufuel...