You can be successful using different media and incubation approaches. My point is that some are less forgiving of mistakes than others. Eggs are always more exposed to all accidents when on the surface than when buried, with drying-out being at the top of the list, and sphagnum increases this risk, especially with small eggs, like chameleon eggs, rather than such as most snake eggs, etc.
While not suggested in this thread, I always advise against "Rubing" things up (a reference to Rube Goldberg, who was famous for making elaborate contraptions to accomplish simple tasks), as it increases the opportunities for things to go wrong. One advantage to finding an area of your house to keep eggs is that the temperatures are far less likely to go haywire than if you have some small incubator that relies on timers, heating elements, etc. If the heat or A/C in you home breaks down, you still have considerable time to react before you lose your eggs. In a small incubator, where a mechanical failure and over-heating are your greatest enemy, the eggs can poach before you know you have a problem.
Since it was mentioned, I also recommend against buying gravid CB females. The overwhelmingly largest factor in your success with eggs is the health and nutritional make-up of the female before she is bred, as successful incubation of good eggs is not hard. Putting females through egg-production if they are not in top-shape is also the most common way we lose females, IMMHO. When you buy a female bred elsewhere, you have yielded those controls and accepted greater risk.
Of course, I could say much more. But that is for another forum ... "tute tute" .... err .... "toot toot"
