The Full Cheek cheek piece, will have the same effect as the traditional Eggbutt in so much as, it will prevent pinching on the sides of the mouth. However the extended pins above and below the bit, firstly prevent the bit being pulled through the mouth and secondly have the effect of guiding the horses head which is great for schooling and training purposes.
The Snaffle is a popular bit due to the curved mouthpiece which distributes pressure more evenly over tongue and bars. With the offset center link it will reduce the nutcracker action and pressure points on the tongue.
The Slow Twist will create more pressure points on the mouthpiece which will make it stronger than the Round Twist and Smooth.