Word to any beginning knifemakers out there: power matters. On the Bader III with a 1.5 hp motor this would have taken hours, and I'd have probably changed belts midway. With the 4 hp grinder I can put much more pressure on the belt, and not only does it do the job much faster, but the extra horsepower means that the belts are useable longer.
Part of this is the nature of the belts themselves. With the modern ceramic belts (I was using Norton ceramic 36 grit) the grit is applied to the belt as a slurry, and as the grit wears away fresh edges of the grit are exposed. With a lower-horsepower motor, though, you can't put enough pressure on the belt to really wear away the abrasive material, and so the sharp edges dull, the belt gets loaded with gunk, and it stops grinding effectively. With the higher horsepower, you can put a lot of pressure on the work without bogging down the motor, and so you can keep using the belts until the abrasive is all gone. A fresh belt still cuts faster, but with 4hp, I can still get quite of life out of a well-worn belt.
For example, for the current belt I'm using, so far I've profiled and ground six tantos, one sword, five knives, and I still have a good amount of grit left.
Between the modern ceramic belts for the coarser grits and the Trizact belts for finer grits, belts are no longer something I need to purchase new for every project. Unnatural, I say, but still preferable to the endless changing of belts I had to do when I first started using larger grinders.