I bought the still air incubator at thanksgiving. My first hatch I followed the directions that came with the incubator, I only hatched 4 out of 23 eggs. So I looked around on this site and I found someone who filled the channels with glass craft marbles, this helps keep a more consistent temperature throughout the incubator. I filled all the channels with water and refilled as my humidity dropped, I also raised the temp from 99.5 to 101. I pulled one red plug at day 7 and the other at day 19. This was better I got 14 out of 32 to hatch. The third hatch I read about dry hatching on backyard chickens. I kept the marbles in the channels but did not add water at all until lockdown. I also left both red plugs out the entire time. I kept the temp at 101. I added water soaked sponges in a few channels at lockdown and placed a straw in one of the smaller holes so I could add water without removing the lid. My hatch rate with the little giant still air using dry hatch was 27/32! And would have been even better but I had 2 malpositions that didn't make it.
Everyone's environment is different but for me dry hatch in the LG still air is the only way I'll hatch from now on.
Good luck!