I've never used an Echo, but I'd love to find something more durable than a Stihl (ok, being sarcastic there). We've had one for over 15 years, and we simply cannot kill it. It's even been run over by the truck a couple of times... never phased it.
The only problem? It's HEAVY. I can't run it for more than 20 or 30 minutes without having to stop for a while... I do have a bad back, yes, but I have *never* lifted any weed eater as heavy as this one.
My adopted dad has two bad shoulders, and has a hard time pull starting anything... he's bought all kinds of weed eaters, and he can't find one that he's able to easily start, and that is light enough for him to carry around and run for 15-20 minutes. Any suggestions there? His weeds aren't particularly big or heavy... they're just in places a mower can't get to. Whenever there's something that requires heavy cutting, I drive up and take care of it for him... with the big weed eater, or a shovel, or an axe... 😀