Buy Echo or Stihl, you will have a 20 year trimmer. I have these or very similar:
https://www.echo-usa.com/Products/Hedge-Trimmers/HC-155
https://www.echo-usa.com/Products/Hedge-Trimmers/SHC-2620S
A little expensive up front, pay now or pay later. I got tired of replacing string trimmers, hedge trimmers and edgers every two years. These are great products, take care of them and they will last years.