The ezDock is garbage. I bought one and promptly returned it. Its huge and clunky and isn't very Windows-compatible (certain ports aren't recognized by Windows unless the unit is re-connected after Windows has been started).
The first thing to realize is that no USB docking station is capable of providing power supply or other fancy things like DVI video. The things to look for are more USB ports (so it serves as a USB hub), an ethernet plug, VGA port (if you use analog video), serial port (for really old printers), audio outputs, PS2 etc.
I looked at the Targus docking station and I must say it looks pretty much worthless. The one I looked at was ugly and had an unwieldly shape, had very few USB ports (1 or 2 I believe), and had no SPDIF output for audio. It did have VGA output, a serial port, PS2 ports, etc - but all of those are antiquated and useless IMO.
I bought a Toshiba Multimedia Center
, which serves as a USB hub, and handles my audio fabulously. It reduces the audio, USB, and ethernet cables that would otherwise be cluttering my laptop to a single USB cable. I still need the DVI and power cables plugging into the laptop, but thats to be expected and they stay out of the way and are easy enough to unplug. The Toshiba unit does cost more, but I feel it's worth it. On the other hand, if you use VGA and serial cables you may lean totally the other way.