Areca may have fixed the LUN/data corruption problem with these beta drivers, but I cannot tell. I will say that the current/retail Lion install doesn't corrupt data, even if it doesn't successfully complete the boot cycle.
My setup is that the boot volume is a RAID 5 array, so the drivers for my RAID card (Areca 1680) must load for the array to be read. That's the problem with the current setup with Lion -- Lion boots from an image then loads another image for the install. Apparently the first image has the drivers but the second image does not (and, as I mentioned in a previous post, I tried to inject the drivers into that second image but it didn't work, apparently).
Anyway, still stuck at the "waiting for root device" error, which I am pretty sure is due to the lack of ArcMSR.kext on the .dmg that the first/boot .dmg loads during boot.
I don't think it's Areca's fault, really. Seems like Apple forgot to include Areca drivers in that second image (maybe they intended to, but didn't get the updated/beta one from Areca, forgot about it, then shipped?). Presumably Apple was aware of this problem since 10.5 had a similar issue with b0rked/missing drivers after the install, but since it didn't boot in this new "Lion way", you could boot off an external drive, copy ArcMSR.kext onto the boot RAID array, then reboot and everything would be fine.
I kind of wish Lion could install to a different drive on the system without rebooting to that drive. If that were true, I could hook up an external, update the RAID array, copy the beta driver to it (if required), and no problem. But this current install/setup sequence with nested .dmgs is