It will depend of your circumstances. If you have a well calibrate NIRS it will be fine, otherwise, and depending of the numbers of animals you are preparing the mix for, you can select the other choices.
Where necessary, use actual values from NIRS. Otherwise, use a margin of safety. Kindly check https://www.feedstrategy.com/animal-nutrition-formulation/managing-nutrient-variability-in-feed-formulations/?amp