Originally Posted by sillyfishyboy
With regards to the PDF query, You should be aware that not all PDF's are created equal.
If you are talking about textbooks / graphically intensive pdf's then dorino's suggestions are correct. Neither device will be great for viewing PDF's and they tend to be quite slow to open.
If however you are talking about novels that have been provided as PDF then it is useful to note that most of these do not have embedded fonts. This means that the fonts are readable as separate to the page rather than being a part or an image. Using the excellent Calibre you can convert these into ePub or any other format you wish. (it does not convert tables and graphics too well which is why textbooks are best left as PDF. Sometimes you will get some odd conversions as it uses character recognition so 'ri' ( r and i ) may be read as 'n' ( letter n ) etc. But on the whole I tend to prefer converting from PDF to HTML as you can get some really odd formatting with HTML files that are a pain to correct.
To add to the conversion about PDFs, I've found they work best on the Sony Reader when they are sized for the reader's screen (3.5 inches by 4.75 inches). When that is the case, I've found that they work very well on my ereader with the ebooks formatted exactly as intended. It is for this reason that I use PDF when formatting ebooks for my ereader (such as those from Project Gutenberg).
It's when the PDFs are not sized for the ereader's screen (such as PDFs that are designed to be printed on standard typing paper). Although reflow makes it possible to read them on my ereader, the results are less than satisfactory since it changes the formatting of the ebook (such as page breaks falling in the middle of pages).