Chosen Solution
I’m looking at buying a used Nikon D4s that the sensor was replaced. I haven’t considered this in my research but I am wondering if this is a good idea or not. The body will come with a warranty and is priced appropriately for what it will come with. Any advice would be much appreciated.
A replaced CCD shouldn’t an issue if it was done properly. If you have access to the camera (with lens) take a grey card with you and take a good set of images of it at different EV levels so you can see the range of the noise at both high and low ISO settings (sensitivity). You’ll also want some graph paper to also shoot to see if you see any aberrations in the parallel lines and the focus is even (make sure the paper is mounted and you hold the camera squarely). If these all look good you shouldn’t have any issues.