There is one best answer. Sight in the way you will hunt. Zeros can be affected by the position you shoot in, and for long range shooting it can make a difference. And, it identifies how far you can reliably shoot and keep the bullet on the target. Lead sleds and the like are the worst for your scope and setting a reliable zero for field use.
For load development, sighting in a new scope, practice for isolating elements of the shot procedure, I will use a bipod and rear bag off a bench or prone.