I have Four set up on my Thompson. It give me the option to run any combination of what the fish tell me they want. Usually it is three or four unless there are some bad currents or I am fishing extra deep, then it is two. If I only had two on the boat than my options are limited. I hope to be installing a kicker this year, this may limit me to a three rigger program but I still will have four on the boat for additional options or to avoid issues due to any failures. .