Depends on the terrain and what you're most comfortable and practiced with.
I've shot way more
predators and deer and antelope with shooting sticks than I ever have from a bipod. But if I have a bipod and the terrain allows me to get prone, I'll take the bipod any time.
A bipod from sitting position is steadier (for me anyway) than shooting sticks are, but if the shots are expected to be quick then I prefer the sticks. They're way quicker to get into position with, and still steadier than a hasty sling.
Deer at 300 from sticks isn't a problem with a little practice. Sitting position, it seems to help a great deal (sticks or bipod either one) when I have something to rest my back against, like a big sagebrush, rock or tree.
Hope that helps.