Hi There,
Like you, I have a D700, it is info repair along with the grip at the moment,
To cut a short story long, Ive had the D700 since it was launched, when the D700 grip failed on the last birding trip away, the wife asked me if I would ever replace the D700,
I said that I would upgrade to a D4s in the near future but repair the D700 first as I could not pass it on unless it was in perfect condition
When I was out shooting that day, the wife ordered the D4s for me and was ready for pick-up when I returned
So, I guess it all depends what your shooting is all about, I find myself always shooting either early morning or very late in the afternoon and low light
shooting BIF, not always but thats my main need, along with grandkids sporting events
Don't need all those pixels and with the big pixel shooting comes storage and handling those huge files
And the management of batteries in the grip is a pain, along with that extra purchase for the grip
If I had the cash flow, I would get both, that is, D4s/D810 combo for the best of both worlds, but I can only justify one body
Like you, I was searching for low shutter count D4 cameras, came across a lot but no low shutter count but couldn't find one
If you hang out for a D4, there is a giant leap in technology, D4 to D4s, not so much
Lastly, remember, glass lasts forever, bodies come and go
.......Gary