I've had my D810 for a week now, replacing my D300. What an incredible upgrade! Here are my first impressions: The form-factor was immediately more comfortable; the improved handgrip in particular feels more secure and therefore steadier in shooting. It's no surprise that button/control operation feels more sure and durable too. At 36 megapixels, the D810 effectively functions as a medium-format digital, but at a fraction of the price. I can crop down to ~30% of full-frame and get a photo quality 8" x 10" print. I love shooting in ISO 64 whenever possible! High ISO noise levels are vastly superior over the D300, which would degrade images markedly by ISO 800. AF in single-point mode is considerably quicker and more precise; my D300 seeks more and does not adjust focus with slight camera movement on macro shots. The monitor is noticeably brighter even in daylight, which should be especially useful in Live View. The D810 has fantastic color rendition, especially at lower ISO. I find that "flat picture control" is excellent for shooting subjects such as polished metal in bright sunlight, without blowing-out the highlights. The quieter/softer shutter produces noticeably less shake. I already see the benefits in hand-held shooting, feeling less jar when I focus/shoot on close subjects. Moreover, the electronic front curtain shutter should reduce shake to nothing in macro photography. The D810 not only produces 3X the image information, but much better image quality when down-sampled to the 12mp resolution of the D300. Obviously, the D810 is making far better use of max. resolution of top lenses such as the 105mm VR micro, the 24-70, and the 70-200. Uploading my full-format NEF files off the card takes about 50% more time than my D300. That's no surprise, but I haven't seen much if any delay in opening/processing NEF files in Photoshop. Granted, my computer is a bit of a beast--an HP Z420 workstation w/ quad processors and 32gb ram, running a 1 TB scratch disk just for Photoshop files. And I appreciate the fact that Adobe was quick to release the D810 DNG converter, Camera Raw upgrade 8.6, as well as the codec that makes D810 NEF files viewable within Windows Explorer. I have also seen a lot of discussion that moving up to a 36mp camera would require more tripod use and/or improvement of hand-held technique. Therefore, I wondered how slow I could go with hand-held shots before the image degrades noticeably? To find an answer, I took a series of hand-held macro shots at a highly detailed subject: George’s eye on the US $1 bill. Here I am using the Nikkor 105mm (VR on) at approximately 1:1.1 magnification. Three shots were taken at each shutter speed, picking the sharpest one; the full-size images below are at 100% crop. There is no sharpening applied or post-processing other than adjusting contrast to ease comparison. Admittedly not a technically perfect test, I gleaned some insight about my shooting style. Obviously, 1/80 shows the effects of hand-held movement at 100%; at ISO 1250 and above, the IQ starts to degrade from noise. While the best result may be @ 1/400, I think I could be satisfied with hand-held results as low as 1/250--especially with a little sharpening applied in Photoshop. Since that’s only about 2/3 stops faster than shooting on my D300, I suspect that no big adjustments on my part will be needed to capture quality images. Full-resolution can be seen here.