At the end of the game you can see your own ranking as well as an aggregated results from the crowd.
I went with the choose favorite/least favorite mechanic because it felt like a better experience then just doing head to head.
With ~20 firms that's a lot of pairs you need to go through.
If you do triplets that reduces the pairs, but it was still too many rounds.
By doing min/max four at a time you can efficiently get implied preferences in ~20 rounds. This make it take only about 3-5 minutes to finish the game!