NiceCopier copies very slowly over the network 2-30 MB/s; Windows 7 32bit Explorer copies the same file at 60-80 MB/s. 3GB file size in this example, but occurs on all files.
The attached screen captures include all for the same file and same source and destination:
NiceCopier window copy stats.
Explorer copy stats.
Windows Task Manager Network throughput stats for 1GB network.