Up until a few months ago I sharpened freehand on a large bench grinder with a CBN wheel. Now I have finally bitten the bullet and got the Sorby pro-edge machine which is, for me, quicker and way easier to get a consistently good grind, without any slight variability that I reckon you will almost always get sharpening freehand.
In fact, the Sorby machine is so good, I have even started sharpening my bench tools (chisels, plane irons, etc) with it, with impressive results. Having always sharpened my bench tools on a diamond plate, I was pretty sure there was no way a machine could get my plane irons as sharp as I could by hand, but it appears I was wrong. Now a quick tickle up with a 600 grit belt and then stropping by hand, and the blades are razor sharp - as good as anything I have used before.