Review on Superior Connectivity: U.S. Robotics USR5633A 56K USB Faxmodem by Tim Thuss

The first warning of the problem came when Windows XP warned me that the drivers for this modem were not signed. The next symptom of the problem was that the connection speed was almost always slower than what I got with my old Creative Labs V90 external serial modem. The last straw was that the drivers crashed after a period of using Windows XP. Maybe it's just my USB 2.0 card. Or maybe it's just the way my machine is set up. But for some reason I couldn't get this modem to work without poor performance and crashes. I have no choice but to return it and either look for another modem or keep using my old one. For what it's worth, I've had mixed results with other USB powered devices in the past. I've been bitten multiple times by devices that draw power over the same wire they use to send and receive data. I would be reluctant to buy such a device again.