Linux (my Ubuntu) seems to have some problems with SMBFS filesystems. I have the USB2-drive of my laptop mounted in a similar fashion as the WD-MyBook, and that has some hangs occassionally too. So I don’t suspect the MyBook (for now).
Other than that, the MyBook isn’t superfast. It’s only connected at 100Mbit now (it has GLAN interface), I don’t know if that will explain it.
The Mionet software on Windows XP stopped working. For some reason it thinks the MyBook is offline. I’ve resetted the drive and the laptop (poweroff -> poweron), but to no change.
Windows Vista has problems with the x-bit in the fileprotections. On Linux my files are created with rwxr-xr-x fileprotection. Probably because of Windows Vista’s excellent (*ahum*) UAC that does not like the execute-bit on external drives, it chooses not to show ANY file with that bit on. Changing the filemode to rw-r–r– does the trick. It took me a while to discover that. Windows XP has NO problem with the execute-bit.
So my first impression: cheap storage, lousy (Windows only) software. No further comments for now.