Right, you can get good 4GB SDHC cards rated for higher speeds, at a lower cost.
The only reason, that I can think of, for a larger card would be if you were to want a
large MP3 library as well as an ebook library.
The current Libre Pro firmware is 20i.
My current 4GB SD card holds 2.99GB as 6,741 Files in 50 Folders, and it is not
noticeably slower in any way. (Both the SD card and the internal memory are formatted
Geeks.com is often a good place to find factory refurbished "geeky" items and last year's
models that were over produced. It's not a bad place to find cheap SD readers, either.