Most Semi-Western hitters use a semi-open stance, facing at roughly a 45-degree angle to the net. This allows for a strong contribution of rotational energy from the legs and torso, producing high racquet-head speeds that enhance both topspin and power, but it also retains some of the advantages of the linearity found in a square stance.
The Semi-Western grip has some trouble with low balls, but not nearly as much as does the Western. It requires a point of contact farther forward than the Eastern, giving you less time to prepare. It can hit flat adequately, but hitting slice is very awkward.
See also: Photo Tour of the Forehand Grips

