Paul: Correct bending of the knees but tummy is hindering the bending of the back and shoulder's follow-through
Pat: Good high toss but ball need not be too far away coz there's a tendency to lean forward forcing a net ball (fault serve).
Jun: A very relaxed serve. The receiving end can relax too coz the ball is coming too slow with a predictable trajectory and bounce.
Goryo: This serve relies on shoulder power. No bending of the back, no bending of knees and only minimal follow through of the shoulder.