I have always used WinSCP to copy file to/from linux based systems. I recently setup a VMware ESXi 5.0 server in my home lab and found myself needing to sometimes copy large files like ISOs or VMDK files to and from the server to my PC. I have heard that FastSCP is much faster then WinSCP and some of my copies were taking 1+ hour so I decided to take a look.
What I found is that FastSCP is indeed faster. Not just a little bit either. I think their claim of 6X faster is actually pretty accurate. I found that to copy about 40GB file using WinSCP took about 1 hour. The same copy using FastSCP took only 8 - 15 minutes on average. See image below:
As you can see from image above FastSCP is pretty fast. It definitely uses the bandwidth available more efficiently.