I have run them all: Fox, Z-Broz, Elka, Walker, etc. For me, the air sprung QRS-3's are the best front shock I have ever put on a sled.
I also ride moto and the small chop that is (in my opinion) best handled by non-air forks just isn't part of the equation on a sled as: 1. Snow provides a lot of that compliance on it's own; and 2. Tracking isn't really an issue on sleds. So, what I look for is quick adjustability, big-hit management, weight, and edgability. Air wins on all fronts.
Rear suspension is a different animal and, for reference, I currently have a '17 and '18 154" 850 where the '17 gets the high-end Z-Broz out back and the '18 gets the Raptor Ace. I have had nothing but poor experiences with years of Tom's/Fox air in the back.