I concur. I have two Stihl saws, both with plenty of plastic. While I do care for my tools and make sure to use them properly (not abuse them), they look like new after a few years of cutting firewood.
If the plastic case pieces are a new thing for Echo, I would avoid them for a year or two to be sure they don't have issues from a new design. Otherwise, you'll be fine.
If the plastic case pieces are a new thing for Echo, I would avoid them for a year or two to be sure they don't have issues from a new design. Otherwise, you'll be fine.