I have recently started using the Army Painter Quickshade for Napoleonics with good results. With all of the questions about painting white on this forum, I thought I'd post the results here!
Here's a close shot of my first model of this unit.
I used the Army Painter white primer, then painted flat base colors with Foundry colors, primarily using the "B" shades of each triad from the paint sets. Then I painted on the Quickshade Strong Tone with a brush. The next day, I highlighted the fleshtone, blue, and white with one quick layer. Finally, I added the mud and finished off the base.
My method isn't as quick as the pure dip method, but this unit went from primer to finished bases in exactly seven days. I don't think the Quickshade will replace my normal black undercoat and three layer method, but for turning out units quickly, it can't be beat!