My rationale for choosing the E model is that occurrence of moiré requires repeating patterns at close to the resolution of the sensor (about 4000 lines or 2000 line pairs per picture height). This is a very rare occurrence in my typical subjects (nature, landscapes, travel documentary, family gatherings). Any subject that is even slightly blurred (eg due to minuscule camera or subject movement or outside the very best depth of field) is exempt from moiré. I’m an amateur and I can live with an occasional picture with moiré. Moiré is correctable, to a degree, in post-processing.
If this rationale applies to you, I recommend the E model. The difference in price is $300 but unlike the non-E model, it comes with a license to use Capture NX2, worth about $150.
About the fly’s eye, did the moiré ruin the photo or make it more exiting? Sometimes we can live with color artifacts. For instance, the tension in curved glass or plastics create interesting patterns with polarizing filters. These are artifacts that may occasionally enhance a picture.
The fine patterned detail of a fly's eyes is a potential concern area for moire but both the camera and post processing can create moire. The moire reduction tools in Lightroom and Capture are both able to handle moire pretty well.
For me, the added detail of the D800E is probably an advantage and outweighs the potential moire on a small number of images.
Thanks, Wesley, it was a very informative article, and I like your site! If I decide on one of these cameras, it'll be the D800E. I'm just not sure yet if I want that many pixels and camera size. Cheers!