Hey, thanks for the info.
CF cards are rare and expensive for their size and I'd have to buy new ones, trying to avoid that. I noticed Mark Lord is successfully running a MSATA->PATA adapter in his current install. I'll try and figure out what chipset is in his and look for a "normal SATA" converter with the same chip.
I briefly looked at a PATA<->SD converter, but saw someone had no success with it, and the converter was overwriting the partition table of the SD card every time it was powered on... too sketchy for me.
I'm good at SMT soldering, I can confidently upgrade the RAM without breaking the player, but if it doesn't help the player software cope better with having lots of files on the thing then I won't bother.
And yeah, the rotary encoder sucks
I don't use it, other than pushing it to shuffle/unshuffle playlists or using it to get into and navigate Hijack. I've got the Empeg sitting beside a standard headunit and fed into its CD changer input.