Summary: This is the SECOND one of these I have purchased. They work so nicely, and contrary to what some say here, I've had it working on Windows Vista AND Windows 7 - haven't tried it on Windows 8 though. Would recommend to anyone.
Summary: I got this as a cheap route to dual monitors and it works great for me. In fact I have two of them. I supposed if you have intense needs like games, it might be a problem, but I have never seen any latency myself. It did break with Windows 8.1 but I got a newer driver and it's fine again. Overall this is an inexpensive way make use of an old monitor you have sitting in your basement to get dual monitors.