Dear Colleagues: I am considering the 5D4 (I have 1Dx and 5D3 and very happy with both). I do stills almost exclusively; video is less important to me. I shoot in very unfriendly environments; outdoors a lot, dust, smoke, dirt, etc. Low light is important, but 14 FPS is probably less so. My question: does anyone (lensrentals, please feel free to chime in!) have any info or thoughts on whether the 1Dx is appreciably more durable than the 5D4? Yes, the 1Dx is a tank, but what makes it tank-like above and beyond the 5D4 (or 3, for that matter?) Do I need to carry the extra weight of 'the tank' for any appreciable increment in durability, resistance to inhospitable environments, etc? Any wisdom, greatly appreciated. Thank you for your time.