I've got the "Industrial" 6" grinder, the yellow one. I bought it "on sale" and it's been a fairly good, if underpowered grinder. But I find my 4.5” grinder works faster for most things.
If I ever get a round tuit, I have been gathering parts to build a belt driven grinder which I feel is vastly superior. This one will run a 2HP industrial GE motor driving a heavy ~1.5" diameter spindle running in Timken bearings with a coarse AO stone on one side, and a 3/4 Super chuck on the other. A second spindle will mount a fine AO and a fine SO wheel. And a third spindle will drive a 72" belt sander patterned on the KMG posted before. I’ve got most of the parts, and machines+stock for the rest, just got to get it done.