I have two major problems with beta4 for C7x0, if they can be fixed or workarounded, I will be able to use beta4 in my Z.
1. Can't bootup without AC Power: I noticed that when the AC cord is not plugged, my Z will turn off during startup at this line:
"can't synthesize pci hotplug events".
Actually my Z will power off shortly (in about 5 seconds) if no AC cord is connected.
2. Suspend doesn't work: After suspend I have to eject the battery and do a full reboot, which in turn is impossible when I don't have AC power.
Of course, if the sound can work it will be "near perfect" for me.