I loved LRFs when I still had my PRS-505. It was the one format that was consistently clean and easily adjustable. Now, however, with my pocket edition 300, LRFs don't work as well. Epub gives me the same effect that LRF did before and since I'm planning to buy another reader at some point, it's a good type to have but that's just me. I did read on an e-reader site that Sony is planning to phase out LRFs as well so it might not be that popular a format in the future either..? :/