@ssholloway: that is odd with KU. I usually don't download KU titles other than direct on Voyage. The only reason to do the download would be to strip DRM and store book for me - which I only do for purchases. I like the new typesetting, so I would be shooting myself in the foot to download the KF8, have the hassle of needing to connect Voyage to computer to transfer, and would only get the old version. For purchases it is worth the hassle, but the Voyage would still get KFX if possible.
Edit: it depends on the book which version you get, even for KU titles. Tested with the book I am reading right now, and it downloaded as AZW3 (
Timebound by Rysa Walker)