I use parallels at work and VMWare Fusion at home (due to a special discount pricing), and between the two, I definitely prefer Parallels. For one thing, I find the interface much cleaner and easier to use than VMware (although VM Ware did improve this quite a bit with their 2.0 release). For another, I have found Parallels integrates with my computer and other hardware much easier and more cleanly than VMWare does. For example, I tried hooking up a GPS unit to a VMWare fusion virtual machine, and had a terrible time trying to get it to even recognize that a device was connected. On the flip side, I have hooked numerous USB devices in through Parallels, including that GPS, and have had no issues whatsoever- I simply plug the device in, select it from the USB menu in parallels, and it is connected to my virtual machine. I have never experienced stability problems with either product, aside from the inherent issues with windows, and I honestly don't know what people are complaining about here, or why they are giving it one-star reviews. From what I have seen using both major products simultaneously, parallels is definitely the better product, although VMWare is (now) decent as well.