Well, you have to run a wire from the machine to your desk. I dont know your setup there but that may be a pain. Also there is the risk of fire, electrical shock (either to you or the mobo), etc. All not real issues, i suppose, but I'll say less elegant.
And the way I read the link, that device plugs into the machine's power then can be turned on my any machine with a web browser. If this machine with the web browser is the second machine, well then yea. However you dont need a machine to monitor the machines. Its the same amount of machines needed for a WOL or LOM setup.
This also adds to the ability to do this anywhere in the world, if required.
Once again, i dont know the setup. The switch may be all that you need. However the features of WOL/LOM or this device make remote administration better and easier. If all you need is to turn it on, your switch should work flawlessly with the caveats I already mentioned, mostly aesthetic and safety.