That used raw NAND flash, which is kind of nasty. I'm not sure they ever quite got it working right before they went under.
Raw NAND is highly preferable to SD or USB drives. You can at least have wear leveling in the OS/FS. SD/USB are bad because most have dumb controllers and just rewrite a page when it changes. Raw NAND is also consistent and meets datasheet specs, whereas SD you never know what you are getting.
What do you mean? I have two of them which work flawlessly...