I have two NAS (Buffalo Linkstation Pro, WD MyBook World), which are connected to 2 PCs with a Gigabit LAN connection. All devices are in "Gigabit mode", meaning all show that their connection speed is really 1 GBit. But the transfer rates to and from the NAS drives are very low, on average 5 MByte/sec, copying large files with several GByte in size.
Looking at the spec of the Buffalo drive, it should do up to 30 MBytes/sec. Of course, this is probably a best case scenario, but I think more than what I have right now should be possible.
Copying files between the two PCs is much faster, about 25 MBytes/sec.
What could limit the data transfer? What can I do to increase it?