We've had quite a few folks asking about TF Version Control's performance, especially in the remote access scenario. Buck wrote up a nice post awhile back on the remote access story; you can still find it here.
The good news is that, even leaving customer needs aside for a moment, the Version Control team has been very motivated to set and meet aggressive perf goals - the Dogfood Team Foundation Server is in Redmond. In the land of main campus, the bandwidth is wicked fast. Like, that kid from The Incredibles fast.
Nearly all of the Version Control is at a remote office in Raleigh, North Carolina. Now, bandwidth in these parts is pretty generous and easy to come by as well (particularly where residential cable modems are concerned), but our network link to Redmond has never been what I'd call wicked fast. In fact, for a long time it was a lot closer to cruelly slow.
One of the features we've developed -- partly due to our own bandwidth woes, but also due in no small part to customer requests and feedback -- is a Version Control proxy server. If you understand what an HTTP web proxy is and how it works, it's a pretty similar concept.
I took over test ownership for the proxy not too long ago, so I've gotten to learn a fair bit about how it works, how it's configured, and of course how much it can improve download performance.
If you've got a set of users with a lot of miles, hopes, or soda-straws-for-bandwidth between themselves and their Team Foundation Server, you'll definitely want to setup a proxy.