When you take into account all the components, the total quality of Purina Flock Raiser appears to be a higher quality for an all flock or adult turkeys. It is not always necessary to use the best feed available as long as the feed used is adequate for the purpose.
If you want to raise long lived healthy turkeys, you want to choose a different feed than for quickly raising turkeys to a processing weight.
Sometimes we have to make decisions over quality vs cost vs availability. Choose the feed that is the most appropriate for your flock. The most important part is to make the decision based on all the information available to you and don't base it on a single component.