I use small grinders to dry cut tiles which means dust, lots of it.
I had an Elu for a while which lasted three or four years, when it died I bought a Ryobi which lasted about 12 months.
I needed a new one in a hurry and went to the nearest Bunnings and bought an AEG for $60, that was almost three years ago and it's still good, no noisy bearings as yet.
I don't know why they're so cheap but I'm not complaining.
The best I ever had was a Protool but they're very pricey.