I use the sax seat all the time when I’m practicing. I find that holding the sax on my right side with the bottom of the horn resting on its little pad works best. No pressure on my neck. Side D is easy to play. Holding the sax between my legs reaching Side D tends to move the horn. Right now I’m practicing “Long as I can See the Light”. The side D’s are easy to reach. The sax seat is used best when recording or practicing and for me that’s all the time since I need to sit when playing the sax.