Olympic style judging is the best, even better is when each model is scored on its own merits before awarding the metals to the scores.
One small armor themed contest I went to in Alberta Canada did such, they even removed each model to a separate room to assign scores without the distraction of the other models. Then to level out the field further the highest & lowest score was omitted from the final tally. If by slim chance (scores taken to the second decimal place) the same score was awarded in a category a second metal (gold, silver, bronze) was awarded.
I know this is impossible for large contests, it was the fairest format I have seen in my limited contest career.
*The worst was where every entrant was asked to judge, assigning 1 winner / category. It seemed the largest model / category won that show...
I skipped the categories that I entered, thinking everyone else did as well.