So I have object that consists of 5 meshes and I want to use material instances for it. Question is do I use 4 instances and the parent or create 5 instances 1 for each mesh.

So I have object that consists of 5 meshes and I want to use material instances for it. Question is do I use 4 instances and the parent or create 5 instances 1 for each mesh.

Yes I understand that but what I want to know is what is better. Using the parent material and 4 instances or leave the parent unused and create 5 instances.

Using instances has certain advantages, so use instances when practicable.