I've been using a homemade incubator for about 6 years, never had a problem with it. Unlike some horror stories I've heard about getting replacement parts, the parts for this one are easy to get. And since there's no standing water, there's no problem with excessive condensation drowning the embryo, and hatchlings don't end up swimming for their lives.
The link goes to my webpage with instructions. It's geared to leopard geckos, but the incubator works for all kinds or reptile eggs.
Gecko Breeding - Eggs and Incubation