Here's the deal - we had one office with 3x bonded T1s, so 4.5Mbps synchronous. Our second, off-site location which just hosts our off-site backups (done nightly) has a business grade cable solution. For 1/15th of what we were paying for the 3x T1s, we figured we could have a blazing fast cable connection, so we got rid of the 3x T1s, and got business grade cable with Comcast.
Both sites are within 2 miles of each other, in the same neighborhood. Both have Comcast cable, business grade, 'rated' at 16x2, but I just did a speedtest in both sites, and they're both at 22Mbps down and around 7 or 8Mbps up.
I would have thought being that they have a much higher up-stream (and down), and plus the fact they're on the same network, only 2 miles (less) apart, that the transfers would be much quicker
...they're not. Since we got the comcast connection, even with NO ONE using either connection, the data transfer from one site to the other is a measely 250Kbps...