The proof is in the manual. Look up your favorite analog modeled plugin manuals and some will mention the level in which it functions best at. As a rule of thumb 0VU or -18dbFS is the sweet spot. This proves that gain staging matters to get the best sound possible from your plugins.
In this Free 4 Step Course you learn colored EQ vs transparent EQ, linear phase EQ vs minimum phase EQ and much more to really help you choose the right EQ for the job.