I have three trimmers and until recently, only one worked, a two year old echo. I decided to fix them or get rid of them. I first overhauled the Sears Brush Wacker. This trimmer uses heavy twisted cord and it will take down trees. Besides new plug, gas lines, carb overhaul and cleaning, the only thing I did was open the exhaust. This is now my favorite trimmer by far. It sounds mean and trims mean. The third trimmer is a Homelite and it runs good but it is an "old ladies trimmer". My Sears sounds like it has a V8 behind it!