I have used the $20 model that Harbor Freight has, and it worked great.
What is so different about this Bosch that it costs 5x more?
More power/torque?? Longer lasting?? Different rpm??
Is the Harbor Freight one 60Hz and the Bosch 120Hz or 240Hz??
I've read so many good things about the HF one that I ran out and picked it up for about $40 - the variable speed one with the case and accessories. Sure enough, failed motor within 20 minutes. Maybe some people have some good ones, but I don't trust HF. There's issues with the bearings or brushes or whatever it is where you can trust a bosch to last you while a HF may easily fail on you.