I'm not a networking expert, so I cannot advice on this. Sorry.

I've only used WinSCP since the speed upgrade, but previously (until it became incompatible with Firefox), I was using FireFTP, and I believe I was getting similar low speeds.
Doing a speedtest (speedtest.net), I was hitting the proper speeds for my internet package every time.
I'm wondering if there's not some setting in either WinSCP or Windows7 that might be hindering it.
I can't really speak for downloads in things like YouTube, as it's hard to tell how fast it actually is, relative to how fast it should be, without a speed reading.

Do you get better throughput using any other client (using the same protocol)?

I recently upgraded from a 25mbps internet service to a 75mbps service, and yet I still am only downloading (using WinSCP) at a rate of 2mbps.

Is there something I'm missing? The speed setting pulldown in the download progress popup window is set to Unlimited. Any other settings I need to change to get a reasonable speed in WinSCP?

Win7Pro