I have been using the kit bench since I started a few months ago. It is the most inexpensive X style bench. It's surprisingly sturdy, and quite comfortable. However the height only goes in big steps - like 2 inches. Two of the steps works for me. I feel the higher step works really well when finger/hands need to jump farther (like in arpeggios), while the lower step works well for controlling dynamics (especially when play softer). But the ideal height seems to fall in between.
So my question is, how picky do you find yourself in setting the bench height? Does plus or minus 1 inch from your ideal height bother you? How would that affect you long term beyond expressiveness, or in terms of fatigue, injury?