The WartHog included instructions are very comprehensive, but I also called and talked to the man who developed WartHog.
10 minutes for first patch. Number of patches depends on volume of shooting. Maybe 4 patches after a few hours of prairie dog shooting, with less time between subsequent patches. Sometimes I give it a few strokes with a nylon brush to loosen the carbon, and WartHog does a great job on carbon, too; so it is all the cleaner you really need.
I haven't tried it after WipeOut, but WartHog is faster and you don't have the mess with that damned foam...and Wipeout foam ate the finish on two of my rifles...I guess they weren't "modern" finishes.