The HF are unreliable at best. My go to unit,,, I know this sounds funny till you try one is the B$D from Walmart or Kmart for 30$, considering the cost they are really good, good power and had one last about 5 years on my bench where it was a daily driver in a fab shop, I doubt a home/hobby shop could wear one out. No point in buying a hi dollar grinder for occasional use but these have really proven out.
What you have to lose for 30$, try one and prove me wrong,, ha, alway keep it as a spare if you don't like it but I would bet once you use one your search will be over.