cheers vortex, I don't use the HUD so am naturally suspicious, the 12 s ND trim is unfathomable but I just feel that somehow the PFD leaves you more in touch with the aircraft and less fixated on the guidance and outside picture.
Using the PFD, your attention would be drawn toward the inside, including the position of the flight controls and you would probably see the trim wheel in motion, whereas using the HUD your attention is drawn towards the visual picture, surely that's the point of it.