No Sony Reader is great for PDFs. The 900 is usable, especially in landscape mode, but the nature of PDFs makes them difficult to adapt to a small screen.

Originally PDFs were designed for 8.5 x 11 inch paper for the express purpose of being able to electronically distribute copy protected documents. They were designed to be printed and not designed to be read comfortably on a computer monitor. As such they often have large margins of 1+ inches all around. Unfortunately they typically don't work well with smaller screen devices like most dedicated eBook readers. IMHO they don't work well with netbook tablet PCs or the iPad either because the screens are too small. There are exceptions of course as some PDFs were designed with a smaller size that better lends itself to a small screen. One example is the manual for my Canon T1i camera wherein the manual is only 3 x 5.5 inches. It works great on my 300.

Questions to ask yourself:

• Does the PDF have large margins that you cannot crop? If yes, it probably won't look good on the 300.
• Does the PDF have two or more columns of text? If yes, it probably won't look good on the 300.
• Is the PDF a poorly done scan of printed material? If yes, it probably won't look good on the 300.
• Can the PDF be converted to a text only format like ePub without destroying its flow of text? If yes, it will work on the 300.