If you have low speed high thrust:stabiliser will be trimmed nose down.
High speed low thrust:stabiliser will move upwards.
To feel the speed stability of your airplane,when in descent,disconnect AP and note the IAS(ie 250 kts),then add SLOWLY some thrust,you will see that the speed is stable at 250 and the thrust increase results in an increase of pitch.
If you increase the thrust faster,the speed will initially tend to increase and the stab trim will trim the stab down and vice versa.