Note that here's a
post that says the Aluratek "apparently" doesn't support ePub links, it only supports PDF links. This presents a reading problem if the ePub book has a lot of footnotes. Also a problem for readers of Calibre newpapers and magazines, who often want to skip past articles. You're limited to serial paging.
Ectaco jetBooks (same hardware platform) have the same problem, but it's difficult to figure out why hardware would affect linking support. Maybe it's just a coincidence that both firmwares have this weakness? Or something weird about the hardware API?