Just came back from Taiwan and bought
Kingston SDHC Class 6 4GB card (Made in Taiwan)
I copy all the ebook (460mb) together with the slow ebook (.lit) files.
Once i on the device and read books, the "Next Page" turning speed is really fast, especially for the .lit files, it took 5 second to go next page on normal SD card
But for me, 4GB SDHC took only 1 second to go next page.
So, what are you waiting for ?? Go to nearest PC Fair and try the SDHC CLASS 6 4GB
( i bought it for NTD 2600, around RM30) hahaha, CHEAP !