Very interesting find @spikeyxxx about the poly counts of mirror modifiers vs linked duplicates. I couldn’t help myself: Had to run some tests myself..
I created a scene using a 12K poly head sculpt. Version A of the scene uses mirror and array modifiers to generate 144 duplicates:

Version B features the same 144 heads generated with linked duplicates:

Version A (linked duplicates) only use 3% of Version B’s memory (modifiers) and renders 40% faster. This info could come in handy for optimizing final DOG renders. And optimizing large scenes in general.