For Window fogging I use a combination that works well. On the outside of the windows, I apply Rain-X, on the inside, I apply Rain-X anti-fog. If you look at my pictures, you can see that I installed 2-12 Volt dual speed fans that clear away the fog very fast while under way. This combination works great. If you do a lot of cooking or coffee brewing, etc, I would recommend a nicro 12V fan be installed in the ceiling above the stove. I have a nicro installed in the forward hatch that also helps cut down on window fogging.
Good luck,
Ben
Good luck,
Ben