I noticed an interesting pattern in the justified comments. All of the remarks I would consider "emotional" were voicing a preference for justified, and disdain for left-aligned:
ragged right edge to be just visually disturbing for me
jagged edges are horrible
left-aligned text is an aesthetic nightmare for me
I can't stand the ragged edge
I didn't notice any such comments in the left-aligned group. Disclaimer: I prefer left-aligned
In any case, the ability to choose fonts, line spacing, indents, and paragraph spacing, etc., are a great thing about ereaders.