Would you say it was reasonable that syncing 125,000 files @ ~18Gb would take just under 4 hours from a laptop with a SATAII disk (5,400rpm) over Gigabit ethernet direct to the DNS-323 with 2 500Gb 7,200rpm drives in RAID1 configuration? No jumbo frames.
Much slower than doing the same over USB2 to a NTFS disk and USB is presumably capable of only 300Mbps.