Here's a small video of how the incubator works for those that aren't familiar with it:
http://www.youtube.com/watch?v=IKSYvEu3MkA
I'm with everyone else and you want your temps as stable as possible. I would be pretty uncomfortable with these temp swings. If I were you, I would build your own out of a styrofoam cooler and use your own thermostat (granted...it'll need to be a nice one, not the hydrofarms sold on amazon). With a good thermostat, the total build should cost you $150 max (~$100 for the thermostat and about ~50 or less for the remaining supplies). Then, once you have it built and it's holding temps at 88-89*, transfer the eggs.