Review on Superior Connectivity: U.S. Robotics USR5633A 56K USB Faxmodem by Charles Phillips

If you have a fast PC and a fast (USB 2.0) USB bus this should work for you. I recommend a powered USB hub for this modem as it requires a lot of power to keep the internal relays open and the phone line open. Some USB sticks only have access to 100mA, and this device requires the full 250mA allowed by the USB specification. It didn't help at all for me: I had to send mine back because it couldn't keep the connection open despite a good quality, powerful USB hub. When it connected once out of many attempts, it was slow and dropped the connection after about a minute. The modem really needs to be "installed and run" in the sense that it should work great the first time. Modems have been around longer than computers, and it's not black magic. The installer must be uninstalled and reinstalled if it does not recognize your modem; it requires too much from the average user and takes time. For comparison, I went to my local store and bought a Zoom 3025, installed the drivers (as they recommend first), installed it in the PCI slot, plugged in my phone cords, and you were done, the computer was zipped up and I was connected; all within half an hour - as opposed to two four-hour sessions with a US Robotics box. If you have a fast PC and a fast and powerful USB connection, you should try this again. It's a nice concept, but it's definitely not backward compatible.