I've decided to write a comparison on the current rasterizing tools for the sony reader (with the emphasis on manga(image)-lrfs)
I've attached the original PDF and the converted files with the article:
For those who just want the conclusion: pdfread creates the smallest files, but the worst images. pdflrf gives much better images, but lacks contrast and creates the largest files (twice as big).
Rasterfarian has the most contrasty and best quality result, and the size is only % larger than pdfread.