I had a cheap weedeater. Actually, I still do, but it is dead.

I went whole hog and bought an FS 90. It is one of their commercial models. I put that fixed steel 3xblade on it, and haven't gone back to line since. I have to wear a face shield, along with long pants, but it pretty much takes care of everything, including trees up to about 2" in diameter. It was just over $300.