Installation of Beta6 from autoupdate on the Z87I Deluxe and the X58A-UD7 went without a hitch while I was at work today, so far as I can tell. I came home to rebooted systems waiting for a password when I hit the function key to wake them. Basic testing on both reveals that the following works:
App Store
audio
networking
iMessage
Movie Player
iTunes
Siri
Sleep/wake cycle auto
Sleep/wake cycle manual
Will leave sleeping tonight and wake them up in the morning to check hibernation.
Asus G751JY laptop also updated itself, but I have not had time to do post install chores on it and get it fully functional yet. It does boot and internet works, battery status works, App Store works and that is about all right now.
EDIT: Hibernate-Sleep/Wake cycle working on both the X58A and the Z87I - after 20 hours both still woke at the touch of the Fn key.