I've burned up two of the $9.95 angle grinders. Their proper application is a wire brush wheel or similar that doesn't need huge torque and won't be run continuous. They are fine for that.
First one the plastic fan disintegrated after 20(?) years of infrequent use cleaning welds with a wire brush wheel. It still ran but I gave it away.
Second one I mounted in the 'cutoff saw mount' from Northern Tool that I described in this recent post:
https://www.tractorbynet.com/forums...-freight-tools-dont-suck-528.html#post5287449
That worked well until it didn't. A couple of minutes running continuous slicing a 7/8" bolt and it faded away, smoking, just as it finished the cut.
I like that cutoff saw mount but I'm a little leery of putting a more expensive grinder in it. I think it needs a very light touch feeding the grinder into the cut.