Hi Tony

Quiklok and Hercules make strong high quality stands. (Many manufactures stands are made by Quiklok and they just stick their own names on)

I suggest you have the Audya on the bottom (So you are looking down at the screen) and the T4 on top. (The T4 can be placed higher because you can angle the screen forward)

The Audya will also be ideal for your left hand chord input, as while not as flexible as the T4 its backing sounds (The live recorded audio loops) are more realistic then the T4 simulated style sounds, whereas the solo and ensemble sounds of the T4 blow the Audya out of the water.

Once you get comfortable with you set-up, look into Midi so as to allow one keyboard to control the other. (You may find that a trumpet and strings layered on the T4 sound great, but a T4 trumpet layered with the Audya strings may sound even better, with same applying to the styles)

In addition by combining them together, you can use the pre-sets to set up both instruments simultaneously, thus enabling you to fully concentrate on playing.

Hope this helps

Bill