Calculating power output during bench press and throw

Measurement of power during bench press using the BMS and linear transducer only is not as problematic as for a movement such as squat jump or power clean as you are measuring the power applied to the bar only. So depending on the level of validity that you require using the linear transducer should be sufficient. If you do have access to a force plate then measuring the force directly by placing the bench on the plate will work well.