It's true that it's silent. That's because it runs at 6fps. I capture the audio separately and synch it up later. It can be tedious but it's a lot less difficult than the cleaning would be. In my experience, the biggest problem with the Workprinters is grain. Whereas a rank transfer smooths out grain and scratches with the water immersion, the workprinter just shines a light on the film and the projector scans it. So although the picture is very sharp (presuming you get a good focus), the sharpness can also manifest as more grain, depending on the type of filmstock used. I've had scans turn out gorgeous, and others turn out pretty grainy.
A month ago I did a scan of a 1952 color film of a drum and bugle corps. Watching it on a friend's big screen TV, the colors leap off the screen - really amazing, it looks like it was filmed yesterday. I also have a scan of a table tennis exhibition from 1972, and it looks like an 8mm home movie. Obviously, your mileage may vary.