Advanced mistake maker
We have 15-20 of them around my work (high end window and door manufacturing with 600+ people employed in 1 million+ sq ft. of building). Them, like any other tool we have there, gets used a lot. Two of them are in my area, and they have held up very well. I think they are probably running 5 hours out of an 8 hour workday, and they still hold up for 3-4 years, even with that kind of use. Brushes and motor bearings are the only items we'd service on them.