I have an Echo curved shaft trimmer and had a hell of a time with it at first b/c the dual line set up strikes the debris shield (NOT the knife edge, the shield above the knife edge) chopping your lines to bits and reducing the 12" cut Dia to about 9"...
Echo sent me a bump line single set up but that kinda sucked b/c the way they set up the line spool made it almost impossible to rewind your own line onto the system with out it tying itself in knots and breaking off inside every time I used it.
I finaly went back to the old 2-line set up and just put a washer under the head to it would stand off a bit more and not hit the debris shield.
That being said, I got a 18V Ryobi (I have a drill, saw, flashlight that all works with the same batteries) last fall and I like it a lot more. It's quite, I don't have to mix gas, I can rewind my own heavier guage line and it will last ~30m on a single charge. I do my 100' driveway, 300+' of fence line, 50+ feet of beds, and a dozen trees all on one charge. My only beef is that their 18V blower eats the battery in about 10m and I can't blow off the entire driveway/patio before it dies and it's not all that powerful.
I have read a lot of good stuff about their new 40V system. If I'd have know about it (it came out this spring) I would have gotten it instead. The battery lasts forever and the blower is a bit more powerful.
Ryobi also has a 24v trimmer, but it's only $20 less and there is no 24v blower. Spend the extra $20 and get the big one. I might sell my 18V system and buy the 40V anyway.
[This message has been edited by agracer (edited 8/11/2012 4:13p).]