I used to own the little brother, the 384 which I upgraded to the state-of the art CF39MS. Image quality of the 384 is the same with some small exceptions. With the CF39 I can use DAC which for the things I do was important. I can also use CF cards which I find handy.
All the other areas the 384 is pretty much the same as the 39. Just smaller. DR is similar, colors, etc..
One thing the 528/384 is way better than the newer versions; the cable & attachment from the image bank to the back. That is so much more pleasurable to use. A smooth round thin flexible cable attached at the corner with some sort of ballhead is making sure you don't really notice the wire when shooting tethered. So much better than the bloody firewire cable with its weird placing and vulnerable chassis part.