Just wanted to get some thoughts from people who have had both cameras.
I shoot a lot of varied stuff from portraits to events, landscape, nature and wildlife (this is where my main interest lies). I upgraded from a 7D to a 5DIII mostly for the better noise handling and full frame sensor despite losing the crop factor advantage. I have been very happy with my 5D3 and I would absolutely love a 1DX for the integrated grip, better weather sealing, FPS and deeper buffer.
The 1DX however is currently not in my budget so I have been kicking around the idea of going from my 5D3 to a 1D4. The only issues that I have run into with my 5D3 are having to wait for the buffer to clear from some action sequences I've taken and the lack of interchangeable focusing screens when I've been using some of my Zeiss lenses and manually focusing large aperture lenses.
Anyone have any thoughts on this crazy idea?
I noticed landscapes in your post above.
If you use wide angle lenses, there is a difference between the 5DIII and 1DIV.
There is the option of a Canon Refurb 1DX. The CPW price alerts work.
I wouldn't expect the retail price of a 1DX to come down anytime soon, nor would I wait in anticipation of this rumored big megapixel body. If the "studio" body materializes, it is aimed at a different segment than the 1DX, so it isn't really a replacement of the 1DX, therefore, the anticipated 1DX price drop may not happen.
Also note that the 1DX does not support the Ec-S screen, and I don't recall seeing anything on this in the upcoming firmware update. That said, I can see a difference looking through 5D series and 1DX viewfinders. The 1DX appears clearer to me and where manual focus was maddening in a 5DII, I can do it through a 1DX (yes, diopter was adjusted in both instances).
There are many posts claiming similarity between the 5DIII and 1DX cameras, and I think they are further apart than what meets the eye or spec sheet. I suspect that a comparison between exploded parts diagram views with part numbers of both cameras would confirm this.
The 1DIV does NOT have the same spot focus feature found on the 7D, 5DIII or 1DX. The 1DIV spot focus feature only works with the supertele lenses with a focus button.
The 5DIII focuses better in low light than the 1DIV. "Low light" is kind of vague, but you may want to try it out if you can with both cameras.
It is hard not to recommend the 1DX.
It is possible that the 1DIV will retain more value over time than the 5DIII, so switching now may not be a bad move.