I bought this sander to replace my 20 year old Craftsman. It is a much better machine, with much less internal friction. It coasts to a stop after several revolutions. The Craftsman stopped in one turn. I'm giving it a "5" in spite of a couple of small manufacturing issues I encountered during setup. One of the holes for mounting the machine to the rotating base was blocked from the casting process, but easily drilled out with a 5/16 bit. The rotating base, although heavy and substantial, wobbles while in use. I wasn't expecting this, but I don't think this will hurt the sanding performance. Also the base has a spring loaded stop pin that easily pulls up to allow it to rotate. The pin is a little too long to retract fully from the locking hole below. So they added a flat nut (jamb nut) to the shoulder, to keep it from screwing in so far (my theory). But that keeps it too high, so the spring loaded pin does not fully engage the locking hole. My fix was to replace the jamb nut with a 1/4" washer that I drilled out to close tolerance so the threads on the 5/16" (or maybe 8mm?) pin would jam tightly into it. It works better. The only other thing I will mention is I added a small bushing cut from 11/64" x .014 brass tubing to the worktable adjustment screws to fill the semicircular slot more fully. Not really necessary, but it makes a closer fit and less wiggle. Other nice features...... -The adjustment levers for the adjustable platforms are levers, not knobs and easier to tighten, but also can be disengaged after tightening to spin them out of the way. - Dust extraction is better than my old one and the dust cover has slotted holes for the mounting screws, making it easier to remove for belt replacement.