It's pretty well reviewed. I'm sure there are more refined machines for a few dollars more, but I think this represents good value. As I'm not going to be doing many other cars, I thought this machine was good enough for who it's for. There are several comparison videos on YouTube, like this one. This guy has done quite a few detailing videos, and seems pretty knowledgeable.
There are 4 areas that get mentioned for potential improvement with this unit. They are:
1) Throw out the backing plate that comes with it. They are off balance, and vibrate terribly. Buy a quality name brand replacement.
2) Disassemble the unit, and replace the grease. The factory grease is cheap, and they don't fill the cavity well.
3) Replace the power cord. It is vinyl, and short.
4) Disassemble the back of the machine and rotate the body so that the switch is on the side of the unit rather than on top.
So the first thing I did was try the backing plate. Sure enough, it has a lot of wobble in it (the shaft appears to not be perfectly perpendicular to the face of the plate). I can't load video of it, so you'll just have to take my word for it. If you buy one of these, it's worth checking out first.
HF must have been listening to customer complaints, because mine came with the switch clocked to the side. No modification required.
I'm going to live with the power cord. I have another work-around for that. And again, I'm not going into the detailing business.
So that just left the grease, which I felt was worth doing. Here we go....