I have operated several 850 case dozers, with the arrangement you describe, one outfit had a pair of these in well kept condition.
I have operated quite a few more of the Caterpillar tractors of the same size or class, pedal steer.
I may have preferred the Cat, but recollecting time spent on both and it was 20+ years ago, either would suffice. I liked the 850 Case, pushed quite a bit of fill with it, as well as fine graded top soil.
I can't recollect how each performed with a full blade full in a turn, in comparison to each other, I believe each performed well, as I would recall something about it if there was something specfic. I can't comment about the mechanical side of it from maintenance or repair, not sure if any of those from that era would have an advantage over the other, could be possible based on design.
I remember the owner of the 850's, his dad was really good at grading with it, topsoil for lawns, his work always stood out.
I think with the 850 and that arrangement, it just took a little time to get used to it. When I did this full time, you kept a ring of keys for all manufacturers, as most places had a variety, some outfits may have stayed with one brand, I recall one I worked for, but most did not.
I would own either brand in that size from that era, not sure how old the 850's were when I ran either of the pair, it was in 1991. One outfit had 80 pieces of equipment at the time and they had Case, JD, Cat, Komatsu in dozers so you eventually got used to all of them as the field super would direct you to various sites throughout the life of the job.
Something about D3's, early ones were pedal steer, ran some of those, but in late '89, and up I can't even recall how many late model ones I ran that were on rental, up to the D4 high track that was just out, that may have been lever steer, 2 levers I recall on one side of the of the operators seat, obviously one side was the blade, It may have been 3 on the one side, 1 for the trans, foward and reverse 3 speeds each, then the 2 levers to the right for steering, those were different. All of the D3s I ran were pleasant to operate in general. Cat went to that rudder like control at some point before joysticks, which I first encountered on Komatsu. The rudder type as I call it would rotate in an arc radius for steering and you would roll the handle within it for speed and direction, and it was still the 3 speed each way power shift, just a different control. I demonstrated a brand new '94 D6 LGP, turned to to a 3 month rental, it had that rudder style control as I called it and it was crisp being new, this one would turn easily with a full blade, though it had the light LGP dozer blade on it.
Joystick really made these nice to operate, last new one I ran was a brand new '04 D4G, that was without hesitation, one very impressive tractor.