Just got my blue 505 and really like it. Fantastic piece of hardware.
I have a few questions, though, if you don't mind humoring a newbie (again).
1. What are ALL the advantages to the LRF format vs RT? I know about file size and TOC ability. Page turn speed is the same. Are there better font options with LRF files? I thought every book on the device used one of the three built in fonts, yet I have a few downloaded LRF files that have a nicer-looking serif font. (Nicer to my eyes, that is.) Looks a little heavier, adding a bit more contrast. I just can't get that look using an RTF file.
Really, the look of the fonts (if I'm right here) is about the only thing that could sway me toward the LRF files. Otherwise, I think I'm an RTF guy...

I'm not terribly impressed with the process of making LRF files. I've not played enough, but the programs (BD especially) seem pretty buggy.
2. How do I minimize the freezing on a file, or the very sluggish changing font size? I've done some reading around here, and it seems that this happens when you've just dumped a book onto the device without using the Sony software. Indeed, the freezing thing usually doesn't happen when I use the Sony software. But there are sometimes exceptions. Like using the Sony software to convert a doc file or copy over a LRF file from either Libprs500 or BD.
Thanks!