I zero with what I intend to shoot off normally, so for range work, that's always a bipod. For field work, I don't find a use for one and shoot of sticks instead, re-checking and altering zero if necessary due to the harmonics being a little different. I've re-stocked both my rifles to straighter recoiling stocks, and find there's less difference, if any at all, between shooting off sticks, bipod or bag. Changing the stock made the biggest difference to my shooting, not the rest that I use. I dislike shooting the 308 in sporting stock guise as recoil has far more of a pronounced effect on how it shoots depending on the steady used. Far less so with my GRS or Boyds stocks.
For range work, I'd prefer a Javelin type bipod but too rich for me so I sick with Harris clones of no more than 9 to 13 inch legs. For field work, a Vanguard T62.