They work better because they have more poles. The rotor makes 1/2 revolution every time the esc switches phase in a 2 pole. 4 poles make a 1/4 revolution, and 6 poles make a 1/6th. That's why they are so smooth even nonsensored. Some esc's wont run sensorless, or will stop if the sensoer wire becomes unplugged or goes bad during a race.