The graphics chip in the HP Dock supports up to 1680x1050 widescreen resolution. However, when running the display in mirror (clone) mode, the external display takes on the same resolution as the built-in laptop screen, which in this case is only 1024x768. Setting the display mode to extend not only allows disparate resolutions on the dual screens, but also gives you double the amount of desktop space to use. Different programs can be opened in each window, just like running dual displays on a desktop.
Using the second display in standard 2D mode such as browsing the internet, using email, word processing, etc. works perfectly fine. Application windows can be dragged from the primary laptop display to the extended monitor fairly smoothly, with only a small amount of lag noticeable on the secondary display that is not present on the laptop screen. Trying to run something that requires a little more graphical horsepower however, such as watching a DVD video, results in a very apparent degradation of picture quality and pixelization. Forget about doing any gaming or other 3D graphical rendering, even if the laptop video card is up to the task the USB dock processor is definitely not. In fact, even just opening a 3D application can cause the display mode to go a bit buggy. Sometimes the Extended setting would revert back to Mirrored mode and require turning it off and back on again to reset.
Bandwidth for other devices seems to be sufficient, such as mouse movements, keyboard strokes and audio output. Although moving large amounts of data through the USB dock, like copying files to and from a flash drive, is somewhat slower than when connected directly to a laptop port. Understandable when you consider that all the information passing through the dock has to share a single 480Mbps (60MB/s) USB 2.0 connection.
I have to say that overall I'm pretty impressed with the HP USB 2.0 Docking Station. After years of dealing with corporate laptops and their proprietary docking station designs, and paying their high prices even for something like a simple port replicator, the universal USB dock sets a new standard for mobile computing. The footprint is smaller, it's easy to setup and use and it's not dependent on any particular brand or model of laptop. For that matter you could use it on a desktop or even a netbook, almost anything with a standard USB port and supported OS. It's great for those with consumer-grade laptops that don't support traditional docking, or those like me who have older laptops with graphics that don't support dual displays. Sure most laptops have ports to connect these external devices, but who wants to have to plug and unplug half a dozen cables every time they move their laptop around?
That said, there are a few features of a traditional notebook dock that the USB dock doesn't support, charging the laptop battery for example. With the HP USB 2.0 Docking Station you still have to hook up your laptop's AC adapter to work for extended periods or to charge the battery while you work. Whereas a traditional dock will typically charge the laptop right through the docking port. Also you may find the graphics on the USB dock to be a limiting factor, whether it's the max resolution of 1680x1050 or the lack of high performance video processing power, the USB bandwidth and graphics chip simply isn't going to handle tasks well like DVD playback, gaming or other 3D applications.
The HP USB 2.0 Docking Station retails for $99 which is about half the price of a traditional hard dock. If you're looking for an easy way to plug your mobile computer into a full size keyboard, mouse and monitor with the convenience of a single connection, or you'd like to be able to extend your desktop across two displays and your built-in graphics chip doesn't support that, well then the HP USB 2.0 Dock provides an inexpensive and easy to use solution.