I used an echo SRM-225 last year, first one the trigger broke, took it back, the second barely made the season, carb problems.
Which is a total shame because the thing was light and held its own as a trimmer, until it didn't. I'd stay away.
Haven't liked the Stihls I've used as much, they've always seemed heavier but that might just be me. Had to replace a carb on my hedgetrimmers this year, and they've been used no more than two seasons. I've got a few stihl handhelds and I'm not so much a fan.
Just purchased a Dolmar 330 C and it seems like a solid machine but only time will tell. The only brand string trimmer I've ever been impressed with after tons of use and abuse is Shindaiwa, but I hear they're being made by Echo now. Go figure. Husqvarna might be a good brand to look into. Love their saws! Whatever you get, have a backup!