Used TightVNC v.1.3.9 on WinXP (both machines) with a LAN (100 Mbit; direct cable connection)
Sending a big file from the Viewer to the Server was reasonably fast; but pulling a big file from the Server onto the Viewer machine was several times slower.
Firewall on Viewer: Comodo 2.4.18.184
Firewall on Server: ZoneAlarm Free 7.462.000
At the next opportunity I will time file transfers over slow dial-up too.